Change cpyamf.util.BBS.has_available to return -1 rather than raise an unnecessary exception.
Change cpyamf.util.BBS.has_available to return -1 rather than raise an unnecessary exception.

git-svn-id: 14367e9ad048ee2de8de43f368ccbd32da08ce87@3386 2dde4cc4-cf3c-0410-b1a3-a9b8ff274da5

thijstriemstra/pyamf,thijstriemstra/pyamf,njoyce/pyamf,hydralabs/pyamf,njoyce/pyamf,hydralabs/pyamf