hi'
I use latest version for test. Some english defines are missing.
http://sourceforge.net/projects/xfr/files/Modules/version_originale/XOOPS%202.5.x/Main.php corrected :
include_once XOOPS_ROOT_PATH . "/language/" . $GLOBALS['xoopsConfig']['language']
. "/calendar.php";
define('_MD_CLEAR_CRITERIA', "clear criteria" );
define('_MD_EXTCAL_1_FR', '1st ' . _CAL_FRIDAY);
define('_MD_EXTCAL_1_MO', '1st ' . _CAL_MONDAY);
define('_MD_EXTCAL_1_SA', '1st ' . _CAL_SATURDAY);
define('_MD_EXTCAL_1_SU', '1st ' . _CAL_SUNDAY);
define('_MD_EXTCAL_1_TH', '1st ' . _CAL_THURSDAY);
define('_MD_EXTCAL_1_TU', '1st ' . _CAL_TUESDAY);
define('_MD_EXTCAL_1_WE', '1st ' . _CAL_WEDNESDAY);
define('_MD_EXTCAL_2_FR', '2nd ' . _CAL_FRIDAY);
define('_MD_EXTCAL_2_MO', '2nd ' . _CAL_MONDAY);
define('_MD_EXTCAL_2_SA', '2nd ' . _CAL_SATURDAY);
define('_MD_EXTCAL_2_SU', '2nd ' . _CAL_SUNDAY);
define('_MD_EXTCAL_2_TH', '2nd ' . _CAL_THURSDAY);
define('_MD_EXTCAL_2_TU', '2nd ' . _CAL_TUESDAY);
define('_MD_EXTCAL_2_WE', '2nd ' . _CAL_WEDNESDAY);
define('_MD_EXTCAL_3_FR', '3rd ' . _CAL_FRIDAY);
define('_MD_EXTCAL_3_MO', '3rd ' . _CAL_MONDAY);
define('_MD_EXTCAL_3_SA', '3rd ' . _CAL_SATURDAY);
define('_MD_EXTCAL_3_SU', '3rd ' . _CAL_SUNDAY);
define('_MD_EXTCAL_3_TH', '3rd ' . _CAL_THURSDAY);
define('_MD_EXTCAL_3_TU', '3rd ' . _CAL_TUESDAY);
define('_MD_EXTCAL_3_WE', '3rd ' . _CAL_WEDNESDAY);
define('_MD_EXTCAL_4_FR', '4th ' . _CAL_FRIDAY);
define('_MD_EXTCAL_4_MO', '4th ' . _CAL_MONDAY);
define('_MD_EXTCAL_4_SA', '4th ' . _CAL_SATURDAY);
define('_MD_EXTCAL_4_SU', '4th ' . _CAL_SUNDAY);
define('_MD_EXTCAL_4_TH', '4th ' . _CAL_THURSDAY);
define('_MD_EXTCAL_4_TU', '4th ' . _CAL_TUESDAY);
define('_MD_EXTCAL_4_WE', '4th ' . _CAL_WEDNESDAY);
define('_MD_EXTCAL_ABSENT', "Absent");
define('_MD_EXTCAL_ACTION_COME', "enrolled");
define('_MD_EXTCAL_ACTION_DELEGATION', "Delegate");
define('_MD_EXTCAL_ACTION_DESINSCRIPTION', "has unsubscribed");
define('_MD_EXTCAL_ACTION_INSCRIPTION', "has subscribed");
define('_MD_EXTCAL_ACTION_MESSAGE', "Left the following message : ");
define('_MD_EXTCAL_ACTION_NONE', "No decision");
define('_MD_EXTCAL_ACTION_NOTCOME', "Will be absent");
define('_MD_EXTCAL_ADDRESS', 'Address');
define('_MD_EXTCAL_ALPHA', 'Alphabetical' );
define('_MD_EXTCAL_AND', 'And');
define('_MD_EXTCAL_APR', 'Apr');
define('_MD_EXTCAL_AUG', 'Aug');
define('_MD_EXTCAL_CATEGORY', 'Category');
define('_MD_EXTCAL_CITATION', "Citation");
define('_MD_EXTCAL_CONTACT', 'Contact');
define('_MD_EXTCAL_DAILY', 'Daily');
define('_MD_EXTCAL_DAY_FRIDAY', 'Friday');
define('_MD_EXTCAL_DAY_MONDAY', 'Monday');
define('_MD_EXTCAL_DAY_NUM_MONTH', '(Day number on month)');
define('_MD_EXTCAL_DAY_SATURDAY', 'Saturday');
define('_MD_EXTCAL_DAY_SUNDAY', 'Sunday');
define('_MD_EXTCAL_DAY_THURSDAY', 'Thursday');
define('_MD_EXTCAL_DAY_TUESDAY', 'Tuesday');
define('_MD_EXTCAL_DAY_WEDNESDAY', 'Wednesday');
define('_MD_EXTCAL_DAY', 'day' );
define('_MD_EXTCAL_DAYS', 'day(s)');
define('_MD_EXTCAL_DEC', 'Dec');
define('_MD_EXTCAL_DEL_IMG', 'Delete the image');
define('_MD_EXTCAL_DESCRIPTION', 'Description');
define('_MD_EXTCAL_DEVISE1', "Livre");
define('_MD_EXTCAL_DEVISE2', "Livres");
define('_MD_EXTCAL_DEVISE3', "£");
define('_MD_EXTCAL_DURING', 'During');
define('_MD_EXTCAL_EDIT_EVENT', 'Edit event');
define('_MD_EXTCAL_END_DATE', 'End date');
define('_MD_EXTCAL_ETABLISSEMENT_ADD', 'Add Location');
define('_MD_EXTCAL_ETABLISSEMENT_ADRESSE', 'Address');
define('_MD_EXTCAL_ETABLISSEMENT_ADRESSE2', 'Address 2');
define('_MD_EXTCAL_ETABLISSEMENT_CATEGORIE', 'Category');
define('_MD_EXTCAL_ETABLISSEMENT_CP', 'Zip Code');
define('_MD_EXTCAL_ETABLISSEMENT_DATE', 'Date');
define('_MD_EXTCAL_ETABLISSEMENT_DEBUT', 'Start');
define('_MD_EXTCAL_ETABLISSEMENT_DELETE', 'Delete Location');
define('_MD_EXTCAL_ETABLISSEMENT_DESCRIPTION', 'Description');
define('_MD_EXTCAL_ETABLISSEMENT_DIVERS', 'Miscellaneous');
define('_MD_EXTCAL_ETABLISSEMENT_EDIT', 'Edit Location');
define('_MD_EXTCAL_ETABLISSEMENT_EVENTS_VENIR', 'Upcoming events');
define('_MD_EXTCAL_ETABLISSEMENT_FIN', 'End');
define('_MD_EXTCAL_ETABLISSEMENT_HORAIRES', 'Hours');
define('_MD_EXTCAL_ETABLISSEMENT_INFO_COMPL', 'Extra Info:');
define('_MD_EXTCAL_ETABLISSEMENT_LIEU', 'Location');
define('_MD_EXTCAL_ETABLISSEMENT_MAIL', 'Email');
define('_MD_EXTCAL_ETABLISSEMENT_MAP', 'Map URL link');
define('_MD_EXTCAL_ETABLISSEMENT_MAP2', 'View Map');
define('_MD_EXTCAL_ETABLISSEMENT_NOM', 'Name');
define('_MD_EXTCAL_ETABLISSEMENT_ORGANISATEUR', 'Organizer');
define('_MD_EXTCAL_ETABLISSEMENT_PRICE', 'Price');
define('_MD_EXTCAL_ETABLISSEMENT_SITE', 'Website');
define('_MD_EXTCAL_ETABLISSEMENT_TARIFS', 'Price');
define('_MD_EXTCAL_ETABLISSEMENT_TEL_FIXE', 'Phone number');
define('_MD_EXTCAL_ETABLISSEMENT_TEL_PORTABLE', 'Mobile Phone');
define('_MD_EXTCAL_ETABLISSEMENT_VILLE', 'City');
define('_MD_EXTCAL_ETABLISSEMENT', 'Location');
define('_MD_EXTCAL_EVENT_CREATED', 'Event Created');
define('_MD_EXTCAL_EVENT_END', 'Have end ?');
define('_MD_EXTCAL_EVENT', "Event");
define('_MD_EXTCAL_EVENTS_FOUND', "%1$s events found" );
define('_MD_EXTCAL_EXPRESSION', 'Expression (list)');
define('_MD_EXTCAL_FEB', 'Feb');
define('_MD_EXTCAL_FILE_ATTACHEMENT', 'Attach a file');
define('_MD_EXTCAL_FORM_IMG', 'Image (%s)');
define('_MD_EXTCAL_FORMAT_DATE', "l dS of F Y h:i:s A");
define('_MD_EXTCAL_FR2', 'Fr');
define('_MD_EXTCAL_ICONE_CLONE', "Duplicate");
define('_MD_EXTCAL_ICONE_DELETE', "Delete");
define('_MD_EXTCAL_ICONE_EDIT', "Edit");
define('_MD_EXTCAL_ICONE_PRINT', "Print");
define('_MD_EXTCAL_IMG_CONFIG', '%s KB max file size, %s pixels width and/or height');
define('_MD_EXTCAL_IMG', 'Image (%s)');
define('_MD_EXTCAL_JAN', 'Jan');
define('_MD_EXTCAL_JUL', 'Jul');
define('_MD_EXTCAL_JUN', 'Jun');
define('_MD_EXTCAL_LAST_FR', 'Last ' . _CAL_FRIDAY);
define('_MD_EXTCAL_LAST_MO', 'Last ' . _CAL_MONDAY);
define('_MD_EXTCAL_LAST_SA', 'Last ' . _CAL_SATURDAY);
define('_MD_EXTCAL_LAST_SU', 'Last ' . _CAL_SUNDAY);
define('_MD_EXTCAL_LAST_TH', 'Last ' . _CAL_THURSDAY);
define('_MD_EXTCAL_LAST_TU', 'Last ' . _CAL_TUESDAY);
define('_MD_EXTCAL_LAST_WE', 'Last ' . _CAL_WEDNESDAY);
define('_MD_EXTCAL_LIB_COME', "Inscription");
define('_MD_EXTCAL_LIB_NONE', "None");
define('_MD_EXTCAL_LIB_NOTCOME', "Unsubscribe");
define('_MD_EXTCAL_LOCALISATION', 'Location');
define('_MD_EXTCAL_MAR', 'Mar');
define('_MD_EXTCAL_MAX_MEMBER_REACHED', 'Maximum membre for this event reached');
define('_MD_EXTCAL_MAY', 'May');
define('_MD_EXTCAL_MEMBERS_LIST', "Members list");
define('_MD_EXTCAL_MO2', 'Mo');
define('_MD_EXTCAL_MONTH', 'month');
define('_MD_EXTCAL_MONTHLY', 'Monthly');
define('_MD_EXTCAL_MSG_0', "%1$s can not be registered");
define('_MD_EXTCAL_MSG_1', "%1$s informs you of its presence");
define('_MD_EXTCAL_MSG_2', "%1$s He informs you that he cancels his visit");
define('_MD_EXTCAL_MSG_3', "%1$s informs you of his absence");
define('_MD_EXTCAL_MSG_4', "%1$s informs you that he cancels his vacation notice");
define('_MD_EXTCAL_NAV_AGENDA_DAY', 'Agenda day');
define('_MD_EXTCAL_NAV_AGENDA_WEEK', 'Agenda week');
define('_MD_EXTCAL_NAV_CALMONTH', 'Calendar month');
define('_MD_EXTCAL_NAV_CALWEEK', 'Calendar week');
define('_MD_EXTCAL_NAV_DAY', 'Day');
define('_MD_EXTCAL_NAV_MONTH', 'Month');
define('_MD_EXTCAL_NAV_NEW_EVENT', 'New event');
define('_MD_EXTCAL_NAV_SEARCH', 'Search');
define('_MD_EXTCAL_NAV_WEEK', 'Week');
define('_MD_EXTCAL_NAV_YEAR', 'Year');
define('_MD_EXTCAL_NBMEMBER_DESC', '0 = no limit');
define('_MD_EXTCAL_NBMEMBER', 'Member limit');
define('_MD_EXTCAL_NO_RECCUR_EVENT', 'Not reccuring event');
define('_MD_EXTCAL_NONE', 'None');
define('_MD_EXTCAL_NOV', 'Nov');
define('_MD_EXTCAL_OCT', 'Oct');
define('_MD_EXTCAL_ON', 'on');
define('_MD_EXTCAL_OR_THE', 'or the');
define('_MD_EXTCAL_OR', 'Or');
define('_MD_EXTCAL_ORDER_BY_ASC', ' Ascendant' );
define('_MD_EXTCAL_ORDER_BY_DESC', 'Descendant' );
define('_MD_EXTCAL_ORDER_BY', 'Order by');
define('_MD_EXTCAL_ORGANISATEUR', 'Organizer');
define('_MD_EXTCAL_PERIODE', 'Periode');
define('_MD_EXTCAL_POLITESSE', "Cordially,");
define('_MD_EXTCAL_PRESENT', "Present");
define('_MD_EXTCAL_PREVIEW', 'Preview');
define('_MD_EXTCAL_PRICE', 'Price');
define('_MD_EXTCAL_RECCUR_POLICY', 'Reccurence policy');
define('_MD_EXTCAL_RECCUR_RULE', 'Reccuring rule');
define('_MD_EXTCAL_RR_DAILY', 'Each day during %u days');
define('_MD_EXTCAL_RR_MONTHLY', 'Each month, the %s during %u month');
define('_MD_EXTCAL_RR_WEEKLY', 'Each week, on%s during %u weeks');
define('_MD_EXTCAL_RR_YEARLY', 'Each year, on%s the %s, during %u years');
define('_MD_EXTCAL_SA2', 'Sa');
define('_MD_EXTCAL_SAME_ST_DATE', 'Same as event start date');
define('_MD_EXTCAL_SEARCH', "search" );
define('_MD_EXTCAL_SEP', 'Sep');
define('_MD_EXTCAL_SERACH_CRITERIA', 'Criteria');
define('_MD_EXTCAL_SERACH_ORDER_BY', 'Criteria');
define('_MD_EXTCAL_START_DATE', 'Start date');
define('_MD_EXTCAL_START', 'Start');
define('_MD_EXTCAL_STATUS_DELEGUE', "Delegation");
define('_MD_EXTCAL_STATUS_DESINSCRIPTION', "Unsubscribe");
define('_MD_EXTCAL_STATUS_INSCRIPTION', "Subscribe");
define('_MD_EXTCAL_STATUS_MESSAGE', "Information");
define('_MD_EXTCAL_STATUS', "Status");
define('_MD_EXTCAL_SU2', 'Su');
define('_MD_EXTCAL_SUBJECT_0', "The maximum number of participants is reached");
define('_MD_EXTCAL_SUBJECT_1', "Presence notification");
define('_MD_EXTCAL_SUBJECT_2', "Cancellation of the notification of the presence");
define('_MD_EXTCAL_SUBJECT_3', "Notification of absence");
define('_MD_EXTCAL_SUBJECT_4', "Cancellation of the notification of absence");
define('_MD_EXTCAL_SUBJECT_COME', "Subscribe of ");
define('_MD_EXTCAL_SUBJECT_DELEGATION', "Delegation of ");
define('_MD_EXTCAL_SUBJECT_DESINSCRIPTION', "Désinscription de ");
define('_MD_EXTCAL_SUBJECT_INSCRIPTION', "Inscription de ");
define('_MD_EXTCAL_SUBJECT_MESSAGE', "Message de ");
define('_MD_EXTCAL_SUBJECT_NONE', "Unsubscribe of ");
define('_MD_EXTCAL_SUBJECT_NOTCOME', "Absence of ");
define('_MD_EXTCAL_SUBMIT_EVENT', 'Submit event');
define('_MD_EXTCAL_SUBMITED_EVENT', 'Submitted event');
define('_MD_EXTCAL_TH2', 'Th');
define('_MD_EXTCAL_TITLE', 'Title');
define('_MD_EXTCAL_TU2', 'Tu');
define('_MD_EXTCAL_URL', 'URL');
define('_MD_EXTCAL_VALIDATE', "Validate");
define('_MD_EXTCAL_WE2', 'We');
define('_MD_EXTCAL_WEEKLY', 'Weekly');
define('_MD_EXTCAL_WEEKS', 'week(s)');
define('_MD_EXTCAL_WHOS_GOING_ADDED_TO_EVENT', 'Added to who's going list');
define('_MD_EXTCAL_WHOS_GOING_REMOVED_TO_EVENT', 'Removed from who's going list');
define('_MD_EXTCAL_WHOSNOT_GOING_ADDED_TO_EVENT', 'Added to who's not going list');
define('_MD_EXTCAL_WHOSNOT_GOING_REMOVED_TO_EVENT', 'Removed from who's not going list');
define('_MD_EXTCAL_WRONG_DATE_FORMAT', 'Wrong date format');
define('_MD_EXTCAL_YEAR', 'year' );
define('_MD_EXTCAL_YEARLY', 'Yearly');
define('_MD_EXTCAL_YEARS', 'year(s)');
define("_MD_EXTCAL_ADD_ME", "Add me");
define("_MD_EXTCAL_CONTACT_INFO", "Contact info");
define("_MD_EXTCAL_EMAIL", "Email");
define("_MD_EXTCAL_END", "End");
define("_MD_EXTCAL_POSTED_BY", "Posted by");
define("_MD_EXTCAL_REMOVE_ME", "Remove me");
/*
define("_MD_EXTCAL_START", "Start");
define("_MD_EXTCAL_URL", "URL");
*/
define("_MD_EXTCAL_WHOS_GOING", "Who's going ?");
define("_MD_EXTCAL_WHOSNOT_GOING", "Who's not going");
_MD_EXTCAL_ICONE_EDIT