conect cisco catalyst 2950t to 3com 4500

[1552]

hello i have a big problem..

how I do to conect a cisco catalyst 2950t to a 3com superstack2 4500..
the problem is when conect de catalys to the 3com... the 3com failure and freeze ( soory I englis is very bad. but I need help),

they dont have any vlan, only admin vlan 1...

and I Attempt to change the speed por example

3com -- int f0/1 speed 100 full duplex
cisco-- int f0/1 spedd 100 full duplez
or
3com int f0/2 speed 10 half duplex
cisco int f0/2 speed 10 half duplex

thank for you help

 

[chipk]

Are you using a crossover cable?