Is it possible to force Linux to use a different /dev designation for a device?

I want to make it recognize my modem as something other than /dev/ttyS14, as the kernel I'm currently using (and that I can't compile more easily than I can learn to use mknod or something else) only supports up to /dev/ttyS13.

I'm about to tear my hair out.

I think it's possible to use an alias in the /etc/modules.conf file, but as for exactly how to do that, I'm not sure.

It's something along the lines of:
alias /dev/ttyS04 /dev/ttyS03

or if the module for your modem is something like lt_modem, you might try:

alias lt_modem /dev/ttyS03


but this is only a guess from reading the modules.conf man page, I may well be wrong.

The problem isn't that I can't let programs access the modem, it's that the kernel is not built with support to detect/use the device...

So you need kernel modules? Or what...? You said you wanted to change designation, I've suggested how to do that. What exactly is it you need?

No. In the kernel config there's an option to set how many 'legacy' serial devices (ttySx--I think these are designated as legacy in this case) are supported. My modem is detected and assigned the node /dev/ttyS14 (known from previous experience), but the kernel the system is using supports only up to /dev/ttyS13, and I don't have the necessary tools to recompile it. I need it to be something other than /dev/ttyS14.

I'm about to try a couple of commands I happened upon on Google..

makedev /dev/ttyS14
mknod -m 666 /dev/ttyS14 c 4 78

Sorry for the lack of clarity. I'm really, really exasperated by this.