Are you with Exetel? They have changed their server last Saturday, not working for me anylonger...
I have also tried your number with Pennytel (I have used 52 prefix to force the call to Pennytel) , no joy:
-- Executing [52131332@internal:1] AGI("SIP/5000-00000143", "selintra|OutCluster|xxxxxxx") in new stack
-- Launched AGI Script /usr/share/asterisk/agi-bin/selintra
-- AGI Script Executing Application: (Set) Options: (CDR(accountcode)=default)
-- AGI Script selintra completed, returning 0
-- Executing [52131332@qrxvtmny:1] AGI("SIP/5000-00000143", "selintra|OutTrunk|xxxxxxxxx") in new stack
-- Launched AGI Script /usr/share/asterisk/agi-bin/selintra
-- AGI Script Executing Application: (Dial) Options: (SIP/131332@PENYTEL||)
-- Called 131332@PENYTEL
[Jul 5 16:00:22] WARNING[5536]: chan_sip.c:2013 retrans_pkt: Maximum retries exceeded on transmission 7ad6218237c67af711da9c750733af52@xxxxxxxxx for seqno 103 (Critical Request) -- See doc/sip-retransmit.txt.
[Jul 5 16:00:22] WARNING[5536]: chan_sip.c:2035 retrans_pkt: Hanging up call 7ad6218237c67af711da9c750733af52@xxxxxxxxx - no reply to our critical packet (see doc/sip-retransmit.txt).
== Everyone is busy/congested at this time (1:0/0/1)
-- AGI Script Executing Application: (Background) Options: (were-sorry)
-- <SIP/5000-00000143> Playing 'were-sorry' (language 'en-gb')
-- AGI Script Executing Application: (Background) Options: (call-cannot-complete)
-- <SIP/5000-00000143> Playing 'call-cannot-complete' (language 'en-gb')
-- AGI Script Executing Application: (Background) Options: (please-hang-up-and-try-again)
-- <SIP/5000-00000143> Playing 'please-hang-up-and-try-again' (language 'en-gb')
-- AGI Script selintra completed, returning 0
== Auto fallthrough, channel 'SIP/5000-00000143' status is 'CHANUNAVAIL'
-- Executing [h@qrxvtmny:1] Hangup("SIP/5000-00000143", "") in new stack
== Spawn extension (qrxvtmny, h, 1) exited non-zero on 'SIP/5000-00000143'
PS: lucky you to still have hairs to rip off.....