...and that's exactly the point. Oracle is suing Google, complaining that they are violating Oracle patents by running Dalvik on Android. Perhaps they'll win, and every app written in Java for Android will become useless.[1]

[1] - Note: not a realistic possibility. Someone would pay a billion dollar ransom instead. But the fact that the threat is out there, regardless how how credible it is, shows the problem.[2]

[2] - Note: the problem in this case is NOT due to non-free implementations: no one questions whether Dalvik is sufficiently free. The problem in this case is software patents. The only proper fix for that is to change the law. Please call your congresscritter.

The other possible fix would be for a Java/Android related alliance to get formed by companies with relevant patent portfolios and sue the crap out of Oracle.

Given their extensive patent portfolio IBM would have had some hope in fighting a fight like that. I don't know that there are many others that have an interest and enough to fight with.

Unfortunately, IBM has sold out to Oracle. Why is that not surprising?

I think "sold out" is way too harsh. I suspect ' more like they got tired of waiting for something that went from "doesn't look like it's going to happen" (but probably realized only after they'd put a fair amount of work into it) into "it will be a cold day in hell...".

Sun demanded a mobile usage restriction. Oracle is suing a company that for technical and no doubt monetary reasons went around this restriction. Oracle now can't make up with Apache without undercutting their lawsuit, even if they were so inclined, which strikes me as unlikely.

Half (or more?) of Apache's contributors are IBM employees. For example: http://harmony.apache.org/contributors.html