MDI with a skin

[Guest]

I have an MDI app written in C#. One the window menu I have typical menu
items, such as Cascade and Tile. They work fine until I enable the skin that
we use. We don't have any third party product for skinning, they had a
consultant write it. I have access to the source code. I am sure the problem
is in there. Using Spy++, I can see that my MDIClient window is getting the
WM_MDICASCADE message. But it is returning failure when processing it. Below
is the log from Spy++. Again, if I disable the skin, it works. Any ideas?

<00001> 006E09BE S WM_MDITILE fuTile:MDITILE_HORIZONTAL
<00002> 006E09BE R WM_MDITILE fSucceeded:False
<00003> 006E09BE S WM_MDICASCADE fuCascade:0000
<00004> 006E09BE R WM_MDICASCADE fSucceeded:False

 

[Guest]

I have confirmed that the MDI Client window is getting its WM_MDICASCADE
message after I call MdiLayout from my main form. I also confirmed that when
the skin is off the child windows do get an MDI_MOVE but when the skin is on
they do not. The child windows are children of the MDIClient window because I
can verify that with Spy++. So what would block the MDI Client window from
sending WM_MOVE to his child windows that might involve a skin?