Looking for tool for configuring routers

Hi,

we're using many different type of routers, from many different
manufacturers. Some need to be configured via SNMP, some via telnet and some
via a serial console connection. I'm looking for a tool with a scripting
language or something else which supports configuring these devices with
predefined configuration files. For example on a cisco oder One Access
Networks router, it should log in via serial console with username and
password, go to conf t mode and enter the config line by line. On an
Efficient Networks router, the cli is totally different with different
prompts etc., and telnet can be used instead of the serial connection
because these routers have a preconfigured ip address etc.

Any Ideas?

Regards,
Jens