I'm running the latest Olegs firmware wl500g-1.9.2.7-d-r2624 (2011-02-19) on a Asus WL-500gP. I use a Huawei E180 USB 3G-modem with the firmware version 11.126.10.00.182.B416
from http://www.dna.fi/yksityisille/asiak...kula_e180.aspx

The setup works otherwise fine but the pppd restarts continiously every few seconds with the following error message:
...
Jun 13 23:33:34 pppd[7930]: pppd 2.4.5 started by root, uid 0
Jun 13 23:33:34 pppd[7930]: tcsetattr: Invalid argument (line 995)
Jun 13 23:33:35 pppd[7930]: Exit.
Jun 13 23:33:35 root: pppd exit code: 1
Jun 13 23:33:37 pppd[7934]: pppd 2.4.5 started by root, uid 0
Jun 13 23:33:37 pppd[7934]: tcsetattr: Invalid argument (line 995)
Jun 13 23:33:38 pppd[7934]: Exit.
Jun 13 23:33:38 root: pppd exit code: 1
Jun 13 23:33:40 pppd[7938]: pppd 2.4.5 started by root, uid 0
Jun 13 23:33:40 pppd[7938]: tcsetattr: Invalid argument (line 995)
Jun 13 23:33:41 pppd[7938]: Exit.
Jun 13 23:33:41 root: pppd exit code: 1
Jun 13 23:33:43 pppd[7942]: pppd 2.4.5 started by root, uid 0
Jun 13 23:33:43 pppd[7942]: tcsetattr: Invalid argument (line 995)
Jun 13 23:33:44 pppd[7942]: Exit.
Jun 13 23:33:44 root: pppd exit code: 1
Jun 13 23:33:46 pppd[7946]: pppd 2.4.5 started by root, uid 0
Jun 13 23:33:46 pppd[7946]: tcsetattr: Invalid argument (line 995)
Jun 13 23:33:47 pppd[7946]: Exit.
Jun 13 23:33:47 root: pppd exit code: 1
Jun 13 23:33:49 pppd[7950]: pppd 2.4.5 started by root, uid 0
Jun 13 23:33:49 pppd[7950]: tcsetattr: Invalid argument (line 995)
Jun 13 23:33:50 pppd[7950]: Exit.
...

The router works fine, but it is very annoying to have the log /tmp/syslog.log filled up with these error messages.

Previously I used firmware version
11.108.03.00.00.B409
on the Huawei E180 USB 3G-modem and then the tcsetattr error messages were not there and the pppd was running stably without restarts. The new E180 firmware has a significantly lower latency and better performance, so I will not go back to the previous one that I used before.

Is this a known problem? Is there a solution or a workaround how to get rid of these error messages?

Best regards. pelle