wmf export small size

[Wolfgang Stoeggl <Wolfgang Stoeggl uibk ac at>]

Using dia v0.94 under Windows XP I experience that exporting my drawings 
to wmf format results in much smaller size of the drawing than it should 
be.
The original drawing has a width of 30 cm and a heigth of 38 cm (scaling 
100).
Export works fine with png and eps (30 x 38 cm) but for wmf I get after 
importing to:

Open Office 1.1.4
width 4,45cm
height 5,64cm

Microsoft-Word 2002
width 4.45 cm
height 5.63 cm

So resizing by a factor of 6.74 is required.
Any ideas? Regards,
Wolfgang

OS: Windows XP prof. german SP2