ports/177077: devel/glibmm does not compile: Unknown component libsigc++20

[Beeblebrox]

>Number:         177077
>Category:       ports
>Synopsis:       devel/glibmm does not compile:  Unknown component libsigc++20
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Mar 18 17:40:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Beeblebrox
>Release:        10-Current
>Organization:
>Environment:
10.0-CURRENT #0 r248373: Sat Mar 16 - amd64
>Description:
/usr/ports> # make -C devel/glibmm
===>  glibmm-2.34.1,1 cannot install: Unknown component libsigc++20.
*** [all] Error code 1

Stop in /usr/ports/devel/glibmm.

>How-To-Repeat:
Above
>Fix:
NA

>Release-Note:
>Audit-Trail:
>Unformatted: