There appears to be something amiss with the Joda library shipped with Play. When using Joda classes from Scala, it gives the error:
error while loading DateTime, Missing dependency 'class org.joda.convert.FromString'
This can be fixed by putting the
Joda convert jar file into your lib folder. There are suggestions on the web that Scala treats optional dependencies like @attributes differently from Java, requiring dependencies that Java would treat as optional. The easiest way round this is to include the Joda convert jar alongside the Joda jar.
I haven't tested this with Play 2.0, but a brief look shows that it doesn't include the convert jar so there's a good chance it's also affected.