Default Arrowhead (PPT 2007)

Using MS PowerPoint 2007 ....

(a) Draw an arrowed line on the page.
(b) Right-click it
(c) Format Shape ... Line Color ... Solid Line ... pick a different
color
(d) Format Shape ... Line Style ... End Type ... pick a different
arrowhead type
(e) Close
(f) Right-click the line and choose "Set as Default Line"
(g) Draw a 2nd (new) arrowed line on the page.

The 2nd (new) arrowed line will successfully have the desired (new
default) color, but will fail to draw the desired (new default)
arrowhead type.

How can we get FULLY custom default charactersitics on arrowed lines
(including the arrowhead)?

Would also be nice if this new default arrowed line applied to new
lines drawn in ALL documents edited with this particular installation
of MS PowerPoint, instead of merely new arrowed lines drawn only in
this document during this editing session (as it appears to do now).