I had a problem with committing changes after merging two branches of my project using TortoiseSVN.
Here are details:
I did a merge branch to trunk of pr
1.3 of TortoiseSVN is very old, the latest revision being 1.5.x. There have been numerous changes in both Subversion and TortoiseSVN since 1.3, so upgrading your client is probably your best bet.
Having said that, 1.5 TortoiseSVN is going to create/update Working Copies to a version 1.5 format. BE VERY CAREFUL when using TortoiseSVN (or any SVN client) against a previous Subversion's working copy.