Below is an example of what happens on Sparc Solaris when two processes try to
build the same package. One process tries to acquire a lock which is held by
another process, then it exits with an error. What is going on here??

=> Lock acquire-depends-lock is held by pid 9860
=> Lock acquire-depends-lock is held by pid 9860
===> Installing dependencies for gtk2+-2.10.12
==========================================================================
The supported build options for gtk2+ are:

        cups debug x11

The currently selected options are:

        x11

You can select which build options to use by setting PKG_DEFAULT_OPTIONS
or the following variable.  Its current value is shown:

        PKG_OPTIONS.gtk2 (not defined)

==========================================================================
/bin/sh: /opt/pkg.obj/x11/gtk2/work.ultra10/.depends: No such file or directory
*** Error code 1

Stop.
bmake: stopped in /opt/pkgsrc/x11/gtk2
*** Error code 1