Merge two attributes in Shibboleth v3

[Rod Widdowson]

> Is that possible in Shibboleth v3 
Yes.
> and if yes how I can make it . 

You need to do some reasonably weird stuff with dependencies and sourceAttributeID.  Read [1] the section on Multi-Attribute Dependencies (and beware that this will all be deprecated in 3.4 where the same stuff will be possible, but the code will be more obvious.

[1] https://wiki.shibboleth.net/confluence/display/IDP30/Dependency