'Call-time pass-by reference' error

Hi,

I'm getting this error:

Fatal error: Call-time pass-by-reference has been removed in C:\xampp-portable\htdocs\convert\class_mdb.php on line 114

I'm a bit of a beginner with PHP classes and the like, and the line in question doesn't seem to seem to reference anything untoward...

It seems like something that may have been superceeded in later PHP versions (I still run an old version on a computer I generally use a script Ive written, but transferring it to a newer computer with a new XAMPP installation, and therefore a later PHP version, on hasn't worked!)

Any chance of a fix?