Double radius accounting

Hi.
I've configured a PPTP server with FreeRadius authentication, and I'm having some problems with authorization: in the accounting table I see a double accounting session for some (random) clients.

My clients are DDWRT routers connecting to a Debian server with pptp version 1.3.4-3. They normally work, but for some connections I see double accounting records. 
The two sessions are almost identical, they differ by just one (or zero) second in the start time.
I don't know if this can matter but in syslog I see the following:

Nov 13 14:47:02 hotspotserver-dev pptpd[15329]: CTRL: Client 212.124.0.2 control connection started
Nov 13 14:47:03 hotspotserver-dev pptpd[15329]: CTRL: Starting call (launching pppd, opening GRE)
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: Plugin radius.so loaded.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: RADIUS plugin initialized.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: Plugin radattr.so loaded.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: RADATTR plugin initialized.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: Plugin radius.so loaded.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: RADIUS plugin initialized.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: Plugin radattr.so loaded.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: RADATTR plugin initialized.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: Plugin /usr/lib/pptpd/pptpd-logwtmp.so loaded.
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: pppd 2.4.5 started by root, uid 0
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: Using interface ppp0
Nov 13 14:47:03 hotspotserver-dev pppd[15330]: Connect: ppp0 <--> /dev/pts/0

Is it normal to see the radius plugin initializaion TWICE?
Is there anything else I can check?

Thanks!

My configs:

/etc/pptpd.conf:
option /etc/ppp/options
logwtmp
localip 10.252.9.1
remoteip 10.252.10.1-254,10.252.11.1-254,10.252.12.1-254
connections 500

/etc/ppp/options:
name pptpd
asyncmap 0
auth
crtscts
lock
hide-password
modem
lcp-echo-interval 30
lcp-echo-failure 4
lcp-max-configure 30
noipx
refuse-pap
refuse-chap
refuse-mschap
require-mschap-v2
require-mppe-128
proxyarp
nodefaultroute
nobsdcomp
mtu 1490
mru 1490
plugin radius.so
plugin radattr.so

/etc/radiusclient/radiusclient.conf:
auth_order      radius,local
login_tries     4
login_timeout   60
nologin /etc/nologin
issue   /etc/radiusclient/issue
authserver      localhost
acctserver      localhost
servers         /etc/radiusclient/servers
dictionary      /etc/radiusclient/dictionary
login_radius    /usr/sbin/login.radius
seqfile         /var/run/radius.seq
mapfile         /etc/radiusclient/port-id-map
default_realm
radius_timeout  10
radius_retries  3
login_local     /bin/login


-- 
Lorenzo Milesi - [email protected]

YetOpen S.r.l. - http://www.yetopen.it/

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