I have internal winmodem v.90 i have to install it on sco 5.05 open server i cant seems to get it detected if i do it manually there is only one option v.34 for toshiba i have a toshiba laptop plz tellme from where i can download the driver and install it this is important

You will most likely not find any availalbe driver for any winmodem... They are Windows-centric by design. You can get an external modem, or a "real" internal modem for fairly cheap.

In general, stay away from all kind of "Win..." stuff.
They win, you lose.
A sad story it is, but there are a few of these supported under Linux, so you may or may not be able to get them to work:

Your particular Losemodem must be supported.
You must be able to port the driver to SCO.

Search on 'Linmodem' - that should get you going ... but I would asess your chances as about 1-5% ...

Linmodems won't work with a SCO box.
Although, if I do turn out to be grossly misinformed, please post back and share with us how you got it working!

I didn't :-)
Also, my old SCO system may not be the same as the more recent ones.
Apart from that, here is the list of _theoretical_ steps you would have to perform, given that you find your particular Losemodem in the Linmodem list.
One more presumption:
The SCO system I have comes with a 'link kit' - that contains a driver skeleton.
I assume the link kit still exists.

Get the source code for the Linux driver.
Extract the modem-specific stuff - make sure you have an internal circular buffer locked in memory.
On each interrupt, update this buffer calling the modem specific routines from the Linmodem driver, make sure that SCO-specific calls are used.

If you keep your tongue straight in your mouth, this is not a very big job, depending on the quality of the Linmodem driver code.

You will probably make some syntactical changes, making sure not to break the semantics.

Then you compile and lin it to the kernel, you will probably have to enter a number and an 'activation key'.

Then, you are 'go'.

Understandably, I have not done this, because I don't think a Losemodem is worth the hazzle, I have 3 normal modems, and I use non of them, because I just got ADSL installed - so now I have 5 good reasons not to do it :-)

But, it _is_ doable ...

Atle