RDP Desktop size not always reported back

[kiilerix]

I have XP running in VirtualBox on a console size 800x600.

When I connect to it with mstsc or xfreerdp and request size 1020x700 by sending

Client MCS Connect Initial PDU with GCC Conference Create Request
header_type: CS_CORE
    Desktop: 1020 x 700, colorDepth: RNS_UD_COLOR_8BPP

then VirtualBox replies with

capability 2, capabilitySetType: CAPSTYPE_BITMAP 0x2
    desktopWidth: 1020
    desktopHeight: 700

BUT the desktop remains at 800x600 and is shown in rdp surrounded by a black border.

When connecting the same way with rdesktop VirtualBox replies with

    desktopWidth: 800
    desktopHeight: 600

and rdesktop thus get a chance to resize properly.

The mismatch and black border has the unfortunate side effect in FreeRDP that some redraw operations fails, for example the zoom effect when windows are mini/maximized in XP.

Is this a bug or a feature in VirtualBox?

If it is a feature: How can we convince VirtualBox to report its screen size back? What is it that makes VirtualBox behave differently in these situations?

VirtualBox-4.0-4.0.0_69151_fedora14-1.i686
Oracle_VM_VirtualBox_Extension_Pack-4.0.0-69151.vbox-extpack 

[Frank Mehnert]

Please reopen if still relevant with VBox 4.1.6.

[bmiklautz]

The problem still exists with version > 4.1.6.

Tested with:

recent xfreerdp from git (gbf02b5b)
mstsc (v 6.1.7601) on windows 7

4.1.18 r78361 on debian
4.1.20 r80170 on osx

Extension pack 4.1.20-80170

[sunlover]

This is a feature of VBox VRDP. See #10888 for a bit more comments.