This used to work:
@startuml !definelong CALL(from,to,funcname) from -[#808080]> to : funcname !enddefinelong !define GREY(x) <color:#808080>x</color> CALL(SDF, MU, GREY(My func)) @enduml
http://www.plantuml.com/plantuml/uml/SoWkIImgAStDuL9CIKtBp4lDoSzBLt1szF7HI2lApzKfoTT9AyrBpalCJTNa0eaew4OhMnY0OAoTGac-WfK2J9vBCJKl1M485yn41VSWrqYD2aq5c-JydFmYAwXskmeRVR207HSNsBvW5pST1TzG7OXwtqgmmPgQN0v0Ou4E1000
But now it does not. You get an internal error.
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