XSL validation

I am trying to verify an xsl file
 
The file worked on windows / IIS - did not work on linux / apache
 
I have found the problem - but it took quite a while - I eliminated code
until I found where the problem was.
 
The problem was
    a semi-colon was missing after an onmouseout stmt
 
I am looking for a better way to validate our files
 
I tried running the file through the validator - it came up with errors on
line 1
 
Are our files incompatible with the validator?
 
If yes, do you have any ideas on how we can best validate our files?
 
I have included the file I am trying to validate
    The error is on line 822 - it is missing a ; at end of line
        onmouseout="style.background='{s1-t1-btn-mst-c}'
 
 
Thank you
 
Gary  - AMI - 262-886-4170