asterisk users - May 2005 - All channels on PRI stuck "Resetting"

Hi,

I've a busy server where one E1/PRI span has been behaving oddly.

Here's the span:

Primary D-channel: 16
Status: Provisioned, Up, Active
Switchtype: EuroISDN
Type: CPE
Window Length: 0/7
Sentrej: 0
SolicitFbit: 0
Retrans: 0
Busy: 0
Overlap Dial: 0
T200 Timer: 1000
T203 Timer: 10000
T305 Timer: 30000
T308 Timer: 4000
T313 Timer: 4000
N200 Counter: 3

Looks good, eh?

But every attempt to make a call on that span fails with status 
CHANUNAVAIL:

May 23 10:22:23 DEBUG[6425]: Launching 'Dial'
May 23 10:22:23 VERBOSE[6425]:     -- Executing
Dial("SIP/monitor-93b6", "ZAP/R0/0824655842") in new stack
May 23 10:22:23 NOTICE[6425]: Unable to create channel of type 'ZAP'
(cause 0)
May 23 10:22:23 VERBOSE[6425]:   == Everyone is busy/congested at this time
(1:0/0/1)
May 23 10:22:23 DEBUG[6425]: Exiting with DIALSTATUS=CHANUNAVAIL.
May 23 10:22:23 DEBUG[6425]: Launching 'Busy'
May 23 10:22:23 VERBOSE[6425]:     -- Executing
Busy("SIP/monitor-93b6", "") in new stack
May 23 10:22:23 DEBUG[6425]: Soft-Hanging up channel 'SIP/monitor-93b6'

As far as I see, all channels are in fact free on that span.

In the end I discovered that all the channels on the span have "PRI Flags: 
Resetting".  For example, "zap show channel 25" gives:

Channel: 25
File Descriptor: 36
Span: 1
Extension: 
Dialing: no
Context: incomming
Caller ID: 
Calling TON: 0
Caller ID name: 
Destroy: 0
InAlarm: 0
Signalling Type: PRI Signalling
Owner: <None>
Real: <None>
Callwait: <None>
Threeway: <None>
Confno: -1
Propagated Conference: -1
Real in conference: 0
DSP: no
Relax DTMF: no
Dialing/CallwaitCAS: 0/0
Default law: alaw
Fax Handled: no
Pulse phone: no
Echo Cancellation: 0 taps unless TDM bridged, currently OFF
PRI Flags: Resetting 
PRI Logical Span: Implicit
Hookstate (FXS only): Onhook

All the channels on the span are stuck this way.

Did anyone see anything similar and have advice?

Thanks,
Steve