Since at least 2005, the combination of PPTP and radiusclient has led to failure of CHAP authentication with the following errors appearing in syslog: rc_avpair_new: unknown attribute 11 rc_avpair_new: unknown attribute 25 I have posted an analysis of the problem and a link to patch set against the CVS tree that fixes it (at least in my hands) at http://www.cardiothink.com/downloads/ The patches also add my name to the copyright: if this is not correct to do please take my name out. Also, I made the library able to use "INCLUDE" as well as "$INCLUDE", fixed what appeared to a problem with high-level directory specifications appearing after (but in alphabetical order) the subsidiary specifications in which they appeared in /Makefile.in, and added a simple program "radlistdictionary" that takes arguments to show the loading and processing of the dictionary and its included subdictionaries, at one of two levels of detail and in one of two forms of output (stdout, syslog). My hope is that this program will be helpful to others in debugging problems of this sort. In this case, the problem because obvious as soon as I ran it although it had been completely opaque before. Please let me know if it would be better for me to post the patches to this list directly rather than to refer to a web link. I don't want to clutter up the mailing list. The patch is 27K uncompressed and 7K compressed.