Strange character conversion when converting XML by XSLT in PHP

I'm converting, or at least trying, one XML file to another XML format using XSLT parsing it with PHP. I'm using a lot of characters in the following style "& #34;", "& #42;", etc. (without the space, added now the prevent any conversion in this e-mail) in the XML file and I would like to keep it that way. PHP is converting every string like these to e.g. "&qout;" or "*". What can be done to prevent this conversion? As far as I understand this is default behaviour of the parser and can not be prevented. Personally I consider this a bug because what if I just want to use "& #34;" (without the space) as a normal string value? The parser shouldn't touch it at all. Can someone enlighten me a bit more on this one? :-) Cheers, Age