PHP3->PHP4 Trouble

I am trying to rebuild existing PHP3 script to work with PHP4.

The biggest issue for now is the following error message:

Warning: Call-time pass-by-reference has been deprecated - argument
passed by value; If you would like to pass it by reference, modify the
declaration of runsearch(). If you would like
to enable call-time pass-by-reference, you can set
allow_call_time_pass_reference to true in your INI file. However, future
versions may not support this any longer. in
/usr/emc/webmail/imp/mailbox.php3 on line 478

What fast solution can be for this problem?

It seems to me that this error message is from PHP3 version.

Sincerely,

Maxim