It has happened.

[hypothermic]

me.kbrewster.exceptions.APIException: This should'nt happen
	at me.kbrewster.mojangapi.MojangAPI.getProfile(MojangAPI.java:63)
	at nl.hypothermic.launcher.AuthHolder.authenticate(AuthHolder.java:297)
	...

Here's a snippet of my code, the exception gets thrown when calling getProfile() in the second line:

AuthenticatedUser user = MojangAPI.authenticate(username, password, clientToken, true);
Profile profile = MojangAPI.getProfile(UUID.fromString(MojangAPI.addDashes(user.getUser().getId())));

Any idea what's going wrong?