MDI Scrollbars not showing

I am converting a regular form into a MDI form by drawing an MDIClient
onto it's client area using the CreateWindowEx function. The style is
WS_CHILD WS_CLIPCHILDREN WS_VISIBLE WS_HSCROLL WS_VSCROLL, the
extended style is WS_EX_OVERLAPPEDWINDOW. The MDIClient gets drawn, I
use SetParent to set it as the parent for my forms, and I am able to
Tile/Cascade them. The problem is that when I move a form beyond the
MDIClient area, I don't get a scroll bar although the window style
specifies it. I have tried initializing the scroll bars by using
SetScrollInfo and setting the min/max range. Does anyone have any idea
where this is going wrong?

Well, the first obvious question is...why are you doing it this way?

The app was originally written with a true MDI parent. I have a copy of the MDI and SDI projects, and want to see the difference in memory consumption. The problems with MDI were as follows:
1. Modality of forms, causing the application to be stateless sometimes. Not a major problem, though.
2. Memory consumption- calling up forms using Load frmName (accessing forms by their global class names) will never unload them from memory even after saying Unload frmName. And since an MDI app is quite stateless, it is hard to use object variables for forms like Dim frm as Form1 and then set frm = nothing because it's hard to figure out at what point to set it to nothing. Setting it to nothing after showing it will reclaim some memory, but causes problems because in a non-modal application, forms have to access other forms objects/controls from within their code using syntax frm1.txt1.text.

I am not sure yet which project I will go with for release. I am still playing around with the SDI one, and then I will compare memory usage.

I hope I make myself clear.

Sarah