Replace caused blank content because of Wrong parameter count for preg_replace()

Running replace on my content caused my content to go completely blank. In the error log, I found the following error:

Wrong parameter count for preg_replace() in \sites\all\modules\scanner\scanner.module on line 877.

Current 6.x-1.0 code includes the use of the count variable on preg_replace, but that was only offered starting with php 5.1.0.
I created this patch to do a version check and if prior to 5.1.0 get the count via preg_match_all() before the replace. This will maintain all current functionality and make it compatible with PHP4.