[ltp] SL-Modem behaves oddly

[S. Donig]

Hi List,

I bought me a R50p several weeks ago. So far most seems to work, except
ppp, which is acting strangely.
R50p's softmodem is compatible with the Smartlink-driver. I'm using
Debian, based on Sarge extended with packages from unstable.
sl-modem-daemon is 2.9.9-1
I've built the kernel-module from sl-modem-source 2.9.9-1
Kernel is based on kernel-source-2.6.7-3 with debian patches

The strange behaviour I mentioned above is as follows:
- establishing a connection takes extremely long, sometimes two to five
retries, often the NO CARRIER-message is displayed,
- without apparent reason connection-speed alters between 2-5, and 8-25
k/s,
- after some time of being connected ppp dies. That may also happen
during a longer lasting download - extremely annoying!

A typical pattern goes like this:
Sep 13 14:47:55 localhost pppd[3419]: pppd 2.4.2 started by [a user]
Sep 13 14:47:55 localhost pppd[3419]: Using interface ppp0
Sep 13 14:47:55 localhost pppd[3419]: Connect: ppp0 <--> /dev/pts/0
Sep 13 14:47:58 localhost pppd[3419]: PAP authentication succeeded
[ IP and DNS-data following]
Sep 13 14:50:28 localhost pppd[3419]: No response to 4 echo-requests
Sep 13 14:50:28 localhost pppd[3419]: Serial link appears to be
disconnected.
Sep 13 14:50:31 localhost pppd[3419]: Connection terminated.
[...]
Sep 13 14:50:31 localhost pppd[3419]: Exit.

The following error-message I received yesterday the first time ever:
Sep 13 16:42:21 localhost pppd[3328]: Connection terminated.
Sep 13 16:42:21 localhost pppd[3328]: Receive serial link is not 8-bit
clean:
Sep 13 16:42:21 localhost pppd[3328]: Problem: all had bit 7 set to 0
Sep 13 16:42:21 localhost pppd[3328]: Exit.

Does somebody use the smartlink driver, and have you ever experienced or
heard of a similar behaviour? (I know for instance at least one other
person, using Fedora Core 2 and having made the same observation.)

Thanks al lot in advance

Simon