Check out the 2.5.212 update on the FTP site.  The changes.txt for
2.5 (changes25.txt) addresses and explains this:
ftp://ftp.iea-software.com/RadiusNT/updates/changes25.txt
> RadiusNT 2.5 Updates and Changes
> -------------------------------
> 
> v2.5.212 - 2/8/00
> 
> * Some CHAP authentications would fail when the CHAP-Challenge was
>   in the attribute, not not packet vector. (RQST00000007312)
> 
> * The trimname feature has been changed to give control over what is
>   trimed and what is not.  The trimname option now has two values that
>   control locally when a domain is trimmed.  This option has NO affect
>   on proxied requests, as each RoamServer has its own trim domain 
>   option.  (This is a Professional/Enterprise feature only.  RadiusNT
>   will still trim spaces from around the username automatically in any
>   version). (RQST00000007204)
> 
>   Trimname:     1 - Trim Domains from Local Authentication requests
>                 2 - Trim Domains from Local Accounting requests
>                 3 - Both 1 and 2.
> 
>   Note:  The older Admin only sets the first option.  You will need to
>          update your RadiusNT admin or edit the trimname value in the
>          reigstry.
> 
--Dale E. Reed Jr. Emerald and RadiusNT__________________________________________IEA Software, Inc. www.iea-software.com
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