[hsflinux] Strange problem with my modem

[t.widjaja1 at ugrad.unimelb.edu.au]

Hi,

I'm using a linmodem with HSF driver (free version). [I'm planning to upgrade
to full version when the problem's fixed]. It's working well, except
that I'm having one strange problem with my modem: (almost) every time 
I disconnect, the modem doesn't know that it is disconnected (ie, it doesn't 
hang up). Namely, the next times I try to connect, the modem says it's busy 
until I disconnect the cable (into the modem) and plug it back in (otherwise, 
I usually have to wait for 2-4 days before I can connect again). This is
especially troublesome because the modem is internal. In addition, I notice
that, when the modem disconnects, the modem manages to hang up if there is
a "clicking" noise coming from the modem (otherwise, it fails to hang up).

When I was using Windows, I didn't have this problem. Any advice as to
how I can fix this up? Any opinion as to what has gone wrong?

I'm using debian with linux kernel 2.4.19. I'm using wvdial to handle the
internet connection. I've also checked that the modem should work well with 
the HSF driver.

Thanks in advance,

Anthony