I just released a tool which validates files committed to Subversion repository - Svn Pre-Commit Validator (short SvnPCV). The tool is written in .NET 2 (C#) and is customisable via XML configuration file.
I decided to write such tool when working on a project where external textural content was edited by non-developers and submitted to Subversion. These content files had to comply to a certain standard, which was rearly the case when i got those, so i had to correct them. So i though it would be good is they just can't commit until the files are valid.
I wrote it and from then on, all the files i got from content editors via svn were perfectly good and i could use them in the software straight away. It saved me a lot of hours.
It's free and the source code is also available. Try it an don't forget to leave your feedback - that's what keeps a developer motivated.
So here it is:
http://wiki.webgear.co.nz/SvnPCV.ashx