ERROR: requested index [-1] out of bounds [13]

I got that error on the top of the page. The debug mode is off. It appears just as soon as you hit enter after finishing typing the web site domain name. If I hit "refresh", then the error appears twice:

ERROR: requested index [-1] out of bounds [3]ERROR: requested index [-1] out of bounds [3]

The last change in XOOPS configuration that I did was the "Xoops Gallery random picture block".

ANY IDEA OF WHAT'S GOING ON? How can I get rid off this anoying ERROR message?

Regards,
Joel Gomez
http://www.rubicon.com.mx