The update to libc6 on the Raspbian distribution which has recently been released can cause the vompclient (and any other program linked to the videocore libraries) to fail with 'library not found' errors. This forum post gives the workaround:
http://www.raspberrypi.org/phpBB3/viewtopic.php?f=66&t=34661
otherwise don't update your system until the problem is fixed.