how come qt4-mac wants to be suddenly upgraded

[Marko Käning]

I just noticed that "port upgrade outdated" wants to install qt4-mac, although it was never in the corresponding MacPorts tree locally.

How can I find out which port is directly to be blamed for this?

I tried

	port dependents qt4-mac

but that command is useless, since it only works on installed ports, whereas qt4-mac isn't installed yet, just wants to get installed due to some other (NEW?) dependency in one of the packages:

$ port installed outdated
The following ports are currently installed:
  cmake @2.8.2_3 (active)
  doxygen @1.7.1_1 (active)
  glib2 @2.26.0_0 (active)
  kmm_banking @1.0_1 (active)
  libpixman @0.18.4_0 (active)
  quvi @0.2.6_0 (active)
  xorg-libsm @1.1.1_0 (active)
  xorg-libXaw @1.0.7_0 (active)
  xorg-libXcomposite @0.4.2_0 (active)
  xorg-libXcursor @1.1.10_0 (active)
  xorg-libXext @1.1.2_0 (active)
  xorg-libXinerama @1.1_0 (active)
  xorg-libXrandr @1.3.0_1 (active)
  xorg-libXt @1.0.8_0 (active)

$port dependents outdated | grep qt4-mac

gives no output, meaning there is no dependency to qt4-mac, so why does it want to be installed in the first place?

See here:

$ sudo port -y upgrade outdated
Password:
--->  Computing dependencies for qt4-mac
For qt4-mac: skipping org.macports.main (dry run)
--->  Computing dependencies for glib2

it's the first port right away. :(

Am a little confused here about this.

How can I clarify here what's going on??