PEAR packages in Drupal modules?

I'm doing feasibility on a project with the working title: 'OpenDocumentPortal' see my Ask Slashdot post for details.

Part of the project requires WebDAV and SVN implementations, for this I have been looking at two PEAR packages:

1. HTTP_WebDAV_Server
2. VersionControl_SVN

I'm not sure about PEAR, it seems poorly implemented and underused. The package manager is certainly not installed on my hosts server (I bet most PHP developers don't even know one exists!). I can only recall using it once, several years ago. So am wondering whether it would be acceptable to use these projects to create Drupal modules. It's certainly possible, but is it 'good practice'? Will I get complaints that I should be using the package manager, or doing things differently?

Am not going to edit the project source files if possible; upstream changes need to be easily managed. The SVN package seems like it's in need of a maintainer though (is this a sign that writing a script in PHP that uses SVN via the exec command is a very bad idea?). These packages are being used instead of the dav_svn package because ODF files need to be intercepted and processed before they are checked-in/out of SVN, if anyone has any ideas of another way to achieve this, what are they?

Thanks in advance for any help.