Hi Rimblock,
i don't want to get you too confused but there are two resources for OFED that I know of: openfabrics.org and Mellanox.com.
with openfabrics release notes for version 3.2, SRP is listed as one of the protocols
https://www.openfabrics.org/downloads/Windows/README
With Mellanox WinOF flavor this protocol is removed "..Removed support for SDP/SRP/WSD"
http://www.mellanox.com/related-docs/prod_software/MLNX_VPI_WinOF_Release_Notes_v3.2.0.pdf
I am not sure what it is but there's got to be a good reason why the folks at Mellanox technologies chose to exclude this protocol from the list. Keep in mind that everything is part of an opensource project and people put untested staff in there. Later on if Mellanox finds that things aren't working, they remove it from their own distribution.
I know it isn't helping you much but the next Mellanox winOF version (4.2 for server 2012) doesn't have SRP support either. on the other hand, IPoIB performance is greatly improved. try running your target/client on regular TCP socket using plane ipoib-ud protocol
I hope it help..