SQL Server Frozen Ghost Cleanup workaround needed
Finally, MS has recognized the issue as a bug: http://support.microsoft.com/kb/2622823

Briefly: It is fixed in 


Sql Server 2008 SP3 CU4
Sql Server 2008 R2 CU10
Sql Server 2008 R2 SP1 CU4


In Sql Server 2012 SP1 I'm not experiencing the issue for more than year of runtime.