v5.3.0 is definitely not supported, the following versions are listed in e-lab: v6.1.2b, v6.2.1b, v6.2.2b
Hi All  We're preparing for a Flare Upgrade to 4.30 from 4.28 on a CX4-120 Storage Array and I'm trying to use the E-Lab Interoperability Navigator.  We have a Dell M1000e Chassis with 2 Dell Brocade SW4424 Module Switches. They are running Fabric OS v5.3.0_emb1. I want to know if I need to upgrade the fabric OS or not. Dell have said that the latest supported Fabric OS version on these switches is v6.1.0h.  I can't find any information on E-Lab Interoperability Manager that tells me which of v5.3.0_emb1 and v6.1.0h is supported and neither from the output from the E-Lab Advisor Website when I upload "supportsave" from the switches.  Can anybody tell me where I can find out what versions of Fabric OS will be supported for our Dell Brocade SW4424 Module switches when we upgrade to Flare 30?  Many Thanks  John
Preparing for a Flare Upgrade: Using E-Lab Interoperability Navigator & 
Compatibility Matrices