[Cooker] Package versioning

[Michael Brown]

What is the 'correct' way to handle version numbers such as "0.7.0pre3" so
that RPM correctly recognises "0.7.0" as being an upgrade to "0.7.0pre3"?  
I'm currently packaging kvoctrain which uses this scheme.  I think I saw
something on a Mandrake web page saying to use "0.7.0.pre3", but I can't
find it anywhere now.

Any help appreciated.

Michael