how to block 1.5 svn client from connecting to the server?

how to block subversion 1.5 client from connecting to the server??. im a开发者_运维百科ble to block 1.4 client ( used python script, mergeinfo capability.). But to block 1.5, which capability should i use? and how to use? please help me

This is hardly possible, as you are relying on new features in SVN to identify client's version. I have looked through new features in SVN 1.6 and don't see any "new properties" - therefore your approach doesn't work here since has obvious fundamental limitations.