About 1/10 of connect attempts to MT PPPoE service from Windows (using builtin XP client or RASPPPOE) fails with PPP 732 error. The problem never appeared with cisco. Is it MT bug? Any fixes/workarounds?

After some tracing I've found that MT incorrectly rejects LCP Code 12 packets. They are recognized as rejects of some random code. If this code is essential (9 for example) Windows drops the connection with 732 error.

Here's how it happens:
[1656] 12:54:12:315: <Protocol = LCP, Type = Identification, Length = 0x14, Id = 0x2, Port = 3
[1656] 12:54:12:315: <C0 21 0C 02 00 12 09 74 17 D8 4D 53 52 41 53 56 |.!.....t..MSRASV|
[1656] 12:54:12:315: <35 2E 31 30 00 00 00 00 00 00 00 00 00 00 00 00 |5.10............|

[1656] 12:54:12:315: >PPP packet received at 07/30/2004 09:54:12:315
[1656] 12:54:12:315: >Protocol = LCP, Type = Code-Reject, Length = 0x14, Id = 0x3, Port = 3
[1656] 12:54:12:315: >C0 21 07 03 00 12 09 74 17 D8 4D 53 52 41 53 56 |.!.....t..MSRASV|
[1656] 12:54:12:315: >35 2E 31 30 00 00 00 00 00 00 00 00 00 00 00 00 |5.10............|
[1656] 12:54:12:315: PPP Code Reject rcvd, rejected Code = 9
[1656] 12:54:12:315: Unpermitted code reject rcvd. on port 3

Code reject packet from MT seems not to conform to rfc1661
conforming packet should look more like C0 21 07 03 00 12 0C 02 00 12 09 74 17 D8 4D 53 52 41 53 56
"The Rejected-Packet field contains a copy of the LCP packet which is being rejected. It begins with the Information field" says rfc1661 but MT begins with LCP DATA field.

So it's MT bug. I hope it'll be fixed soon

You are correct, this is a bug. It will be fixed in v2.8.13 . v2.9 beta does not have this problem though.

John