Open Source in commercial software products (Score 1)

Have you ever experienced the situation where a client would not allow open source packages, such as Xerces, to be used for an implementation? In particular, the lack of indemnification clauses against 3rd party intellectual property claims in open source licenses, found in most commercial licenses, seems to be worrisome for clients. This question also has relevance with regard to the recent SCO/Linux commotion.

Has your company chosen to legally vouch for open source packages? Did you have to replace open source packages by homegrown or commercial products?