Although I just use svn to checkout just to let you know guys :-
Older clients and servers interoperate transparently with 1.4 servers and clients. Of course, some of the new 1.4 features may not be available unless both client and server are the latest version. There is no need to dump and reload your repositories; Subversion 1.4 can read repositories created by earlier versions. To upgrade an existing installation, just install the newest libraries and binaries on top of the older ones.
Subversion 1.4 maintains API/ABI compatibility with earlier releases, by only adding new functions. A program written to the 1.0, 1.1, 1.2 or 1.3 API can both compile and run using 1.4 libraries. However, a program written for 1.4 cannot necessarily compile or run against older libraries.