OpenBSC GPRS Question

Hello All, Tried to setup Osmo-NITB + OsmoSGSN + GGSN installation using sysmoBTS station. To connect to the network I use custom SIM card programmed with appropriate MCC and MNC. That is what I get: osmo-nitb log: ==================== <0005> abis_nm.c:2414 OC=GPRS-CELL(f1) INST=(00,00,ff) IPACCESS(0xf6): SET ATTR ACK <0005> abis_nm.c:2414 OC=GPRS-NSVC(f2) INST=(00,00,ff) IPACCESS(0xf6): SET ATTR ACK <0004> abis_rsl.c:1431 (bts=0,trx=0,ts=0,ss=0) Activating ARFCN(666) SS(0) lctype SDCCH r=LOCATION_UPDATE ra=0x0f ta=0 <0004> abis_rsl.c:1165 (bts=0,trx=0,ts=0,ss=0) CHANNEL ACTIVATE ACK <0000> abis_rsl.c:1621 (bts=0,trx=0,ts=0,ss=0) SAPI=0 ESTABLISH INDICATION <0002> gsm_04_08.c:1055 LOCATION UPDATING REQUEST: mi_type=0x01 MI(250770000002339) type=NORMAL <0001> gsm_04_08.c:119 (bts 0 trx 0 ts 0 pd 05) Sending 0x18 to MS. <0000> abis_rsl.c:1621 (bts=0,trx=0,ts=0,ss=0) SAPI=0 DATA INDICATION <0003> bsc_api.c:479 CLASSMARK CHANGE CM2(len=3) CM3(len=9) <0000> abis_rsl.c:1621 (bts=0,trx=0,ts=0,ss=0) SAPI=0 DATA INDICATION <0002> gsm_04_08.c:462 IDENTITY RESPONSE: mi_type=0x02 MI(358279013039780) <0002> gsm_04_08.c:426 -> LOCATION UPDATE ACCEPT <0001> gsm_04_08.c:119 (bts 0 trx 0 ts 0 pd 05) Sending 0x02 to MS. <0002> gsm_04_08.c:768 -> MM INFO <0001> gsm_04_08.c:119 (bts 0 trx 0 ts 0 pd 05) Sending 0x32 to MS. <0002> gsm_subscriber.c:361 Subscriber 250770000002339 ATTACHED LAC=1 <0000> abis_rsl.c:1621 (bts=0,trx=0,ts=0,ss=0) SAPI=0 DATA INDICATION <0002> gsm_04_08.c:1071 TMSI Reallocation Completed. Subscriber: 250770000002339 <0000> chan_alloc.c:405 (bts=0,trx=0,ts=0,ss=0) starting release sequence <0003> gsm_04_08_utils.c:231 Sending Channel Release: Chan: Number: 0 Type: 1 <0004> abis_rsl.c:633 (bts=0,trx=0,ts=0,ss=0) DEACTivate SACCH CMD <0000> abis_rsl.c:1621 (bts=0,trx=0,ts=0,ss=0) SAPI=0 RELEASE INDICATION <0004> abis_rsl.c:679 (bts=0,trx=0,ts=0,ss=0) RF Channel Release CMD due error 0 <0004> abis_rsl.c:731 (bts=0,trx=0,ts=0,ss=0) RF CHANNEL RELEASE ACK ===================== Thus, I see that GPRS attributes were set successfully and the subscriber was granted access to the network. Then, I look into osmo-sgsn log: ===================== <0010> gprs_ns.c:679 NSEI=101 Rx NS RESET (NSVCI=101, cause=O&M intervention) <0010> gprs_ns.c:538 NSEI=101 Tx NS RESET ACK (NSVCI=101) <0010> gprs_ns.c:679 NSEI=101 Rx NS RESET (NSVCI=101, cause=PDU not compatible with protocol state) <0010> gprs_ns.c:538 NSEI=101 Tx NS RESET ACK (NSVCI=101) <0010> gprs_ns.c:865 NSEI=101 Rx NS UNBLOCK <0010> gprs_ns.c:865 NSEI=101 Rx NS UNBLOCK <0011> gprs_bssgp.c:1000 NSEI=101/BVCI=2 Rejecting PDU type 1 for unknown BVCI <0011> gprs_bssgp_util.c:103 BSSGP BVCI=0 Tx STATUS, cause=Unknown BVCI <0011> gprs_bssgp.c:1000 NSEI=101/BVCI=2 Rejecting PDU type 1 for unknown BVCI <0011> gprs_bssgp_util.c:103 BSSGP BVCI=0 Tx STATUS, cause=Unknown BVCI ===================== So, PDU is rejected and I don't see any GPRS availability on a phone. Has anybody ever seen this message? Regards, Sergey.