So I’m not an early adopter but after updating my personal Mac to Mavericks with little issues, I decided to upgrade my work Mac as well.
Besides Mavericks not shipping with Java and breaking all my hard work with Jasper Reports, I soon after discovered that it had also upgraded my Subversion to 1.7 which stopped me from being able to check in my code.
So I found this little tip from Kevin Broome that fixed my issue quickly.  I figured it could be done but Keven actually found where the old SVN 1.6 lived on the hard drive.
To summarize:
1) Make a backup of your SVN 1.7
sudo mv /usr/bin/svn ~/Documents/svn_1.7
2) Point to 1.6 in paths
sudo nano /etc/paths
3) Add the following to paths
/Applications/Xcode.app/Contents/Developer/usr/subversion-1.6/bin
4) Check SVN version
svn help
That’s it, you should see Subversion 1.6