Different units in svg header with units in document properities

[LordBlick]

Inkscape 0.47 r22583/PLD Linux
I'd prefer mm units in my projects, so usually I'm set it as default in document properties. Why it is not set in <svg width="XXmm" height="XXmm" as described on http://www.w3.org/TR/SVG11/types.html ? If it will be implemented, other "dirty" default units definitions maybe can be omitted...
If I save document as clean svg, I've got a trouble with it...

Quote :
When lengths are used in an SVG attribute, a <length> is instead defined as follows:

length ::= number ("em" | "ex" | "px" | "in" | "cm" | "mm" | "pt" | "pc" | "%")?

[su_v (suv-lp)]

Setting the default units in 'Document properties' adds
  <sodipodi:namedview (…) inkscape:document-units="mm" (…) >
and leaves the <svg> attributes 'width and 'height' unitless (Inkscape in this case uses px).

Default templates with custom units however do have the units added to the SVG width and height attributes.
<http://www.w3.org/TR/SVG11/struct.html#SVGElementWidthAttribute>

[Matthew Petroff (matthewpetroff)]

As of r12554, setting the page size units in document properties changes the SVG width and height units.