PHP error on Joomla powered site

[webmaster.lu2wa64]

Hi All,

Since I've read Corey's post about changes being made to Boru server (where my site is hosted) I want to report that an error (warning) has taken the place of my site's main menu. It states the following:

Warning: Parameter 1 to modMainMenuHelper::buildXML() expected to be a reference, value given in /home/*****/public_html/libraries/joomla/cache/handler/callback.php on line 99

(user name made *****)

No main menu and no resources menu. The site is built around Joomla 1.5.14. I've made no changes during the last week.

I don't know if this is temporary or I should start searching for a problem in php or something.

Thanks in advance!!!

[webmaster.lu2wa64]

I don`t think this is related to the PHP 5.3 upgrade that took place recently because I have another copy of my site hosted on chopin server and it works ok (same versions of everything on boru and chopin).
Any idea?

Thanks!