Brocade SAN Fabric Auto Negotiation Not working

Hi,

We have a critical situation at the office using Brocade M48 (4gb) and Brocade DCX (8Gb) devices with a suspected known auto-negotiation issue fixed in code level 6.4.3.c on the M48. The fix was to lock all ports to 4Gb to correct the issue.

Any of you experience this issue ?

Mike