PDP激活失败，空口上发现大量的Immediate assignment reject，可能原因是？

PDP激活失败，空口上发现大量的Immediate assignment reject，如何分析？可能原因是什么？站点GPRS不可用，话务不高，为了排查问题，配置了4条静态PDCH，就一个站问题，基本可排除资源导致；无线环境良好，无语音问题。 是否还有其他可能原因？ 请各位帮忙。消息内容如下：
MS1
Immediate Assignment Reject
Time : 00:58:21.90
Vendor Header
L2 pseudo length : 19
Skip indicator : 0
Protocol discriminator : (6) Radio resources management messages
Message type : 58
Page mode
Page mode : (0) Normal paging
Request reference
Random access representation : 127 (7F hex)
Establishment cause : Answer to EGPRS Packet Channel Request
FN modulo 42432 : 28256
Representation : T1' = 21, T2 = 20, T3 = 2
Wait1 : 30
Request reference
Random access representation : 127 (7F hex)
Establishment cause : Answer to EGPRS Packet Channel Request
FN modulo 42432 : 28256
Representation : T1' = 21, T2 = 20, T3 = 2
Wait2 : 30
Request reference
Random access representation : 127 (7F hex)
Establishment cause : Answer to EGPRS Packet Channel Request
FN modulo 42432 : 28256
Representation : T1' = 21, T2 = 20, T3 = 2
Wait3 : 30
Request reference
Random access representation : 127 (7F hex)
Establishment cause : Answer to EGPRS Packet Channel Request
FN modulo 42432 : 28256
Representation : T1' = 21, T2 = 20, T3 = 2
Wait4 : 30
RestOctets
extRA3 : 11

Message dump (Hex):
06 3A 00 7F A8 54 1E 7F A8 54
1E 7F A8 54 1E 7F A8 54 1E 2B
2B 2B

问题补充：2011-9-23 01:01
偶尔收到以下内容：
MS1
Immediate Assignment Reject

Time : 00:58:22.64
Vendor Header
L2 pseudo length : 19
Skip indicator : 0
Protocol discriminator : (6) Radio resources management messages
Message type : 58
Page mode
Page mode : (0) Normal paging
Request reference
Random access representation : 122 (7A hex)
Establishment cause : One phase packet access with request for single timeslot uplink transmission; one PDCH is needed
Random reference : 2
FN modulo 42432 : 28355
Representation : T1' = 21, T2 = 15, T3 = 50
Wait1 : 30
Request reference
Random access representation : 122 (7A hex)
Establishment cause : One phase packet access with request for single timeslot uplink transmission; one PDCH is needed
Random reference : 2
FN modulo 42432 : 28355
Representation : T1' = 21, T2 = 15, T3 = 50
Wait2 : 30
Request reference
Random access representation : 122 (7A hex)
Establishment cause : One phase packet access with request for single timeslot uplink transmission; one PDCH is needed
Random reference : 2
FN modulo 42432 : 28355
Representation : T1' = 21, T2 = 15, T3 = 50
Wait3 : 30
Request reference
Random access representation : 122 (7A hex)
Establishment cause : One phase packet access with request for single timeslot uplink transmission; one PDCH is needed
Random reference : 2
FN modulo 42432 : 28355
Representation : T1' = 21, T2 = 15, T3 = 50
Wait4 : 30
RestOctets
extRA3 : 11

Message dump (Hex):
06 3A 00 7A AE 4F 1E 7A AE 4F
1E 7A AE 4F 1E 7A AE 4F 1E 2B
2B 2B

贴上来的消息里应该没有携带故障原因,GPRS为什么不可以用?如果GPRS都不能用,EDGE也是不能用的(看信令你请求的EGPRS,也就是EDGE).建议查看告警和话统,这四个静态PDCH信道是否正常,有没有人占用过?另外每个信道的TBF平均个数是多少?呵呵

造成Immediate assignment reject最常见的原因一般都是信道拥塞或硬件故障造成的，你上面说“GPRS不可用”不知道是否是查询过的，PDP激活本来就是使用GPRS业务时才出现的状态，如果GPRS都不可用了，那相应的PDP也就无法激活成功吧，附的消息也不能完全看懂，希望有高手能将消息讲解下，继续学习。