SSH from Procurve to Cisco

Hi,

I am using a Procurve Switch as an Out of band management switch and in the event our jump box on the out of band management LAN fails, I would like to be able to SSH into our Cisco switches from the CLI of the Procurve as a last resort.

This is currently working fine for all the access switches (2960X's) but doesn't work for the core switches (3750X's).

I get this:

OOB-PROCURVE# ssh user@x.x.x.x The SSH connection failed: Unexpected error. OOB-PROCURVE# 

Any ideas why this is working for the 2960's and not the 3750's?

I have a feeling its to do with ciphers but am not sure.