RelatedRecords "Deprecated: Function split() is deprecated"

Hi. I'm attempting (unsuccessfully) to recycle some code I used on another site that utilizes the 'Related Record Lookup Functions' beta plugin. On the new site, running PHP 5.3.13, I am seeing the following error that does not appear on the older site running PHP 5.1.4:

"Deprecated: Function split() is deprecated in /mysite/htdocs/cmsb/plugins/relatedRecordLookupFunctions.php on line 66"

I am not entirely ruling out my own coding errors, but searching on Google, I think this might be the issue:
http://php.net/manual/en/function.split.php

I realize this plugin is a beta, but would like to get my related records to display for the new project with whatever is considered best practice. I'm also concerned that if my hosting company upgrades the old site that the plugin code will break there.

Any help would be appreciated and if my code is suspect, I'd be happy to post that, too.

Thanks in advance. ~ Deborah