I just built a new VM with CentOS 5.1 and have the same problem, so the broken Scalar must be in that version aswell. Just setting up another VM with the 5.0 CentOS release. Hopefully that will cure it. Certainly has been a interesting exercise! and my fiancee is needing her email back soon
Well one good thing out of all of this, have learnt a lot about Zimbra
Will keep you posted, but I bet a long night ahead.