I have a system with gprs modem connected.
After connecting to the gprs network I start pppd.

It works fine on AMD LX600 CPU (366MHz Pentium class)  but it fails with STCP Atlas (120MHz 486 class).

The difference is that with slower CPU interface doesn't get it's IP address. I see no reason for this. I have checked 
sloginfo log to see if there are any missed characters on serial line - but there are none.

I am attaching logs from syslog. 

The only difference in syslog is in these two lines:
Feb 11 11:01:50 nto pppd[3842127-1]: rcvd [IPCP ConfReq id=0x3 <addr 85.102.119.136>]
Feb 11 11:01:50 nto pppd[3842127-1]: sent [IPCP ConfAck id=0x3 <addr 85.102.119.136>]

They are present in fast system and missing in slow system.

Any idea where the problem could be?

Thanks, PKY