Image resize command in a button does not work

This button does not work:

Image WIDTH=400 PRESERVEASPECTRATIO REPLACE HERE 

While this works perfectly:

Image ROTATE=90 REPLACE HERE

I need to resize larger images to a width of 400, keeping the aspect ratio.
Hmm, am I really stupid and doing something wrong or it's a bug?

Adding CONVERT on the end seems to fix things, although I don't think you were doing anything wrong based on what the manual says. We'll look at the code and correct the manual or the code, whichever turns out to be wrong, but here's a workaround for now:

Image WIDTH=400 PRESERVEASPECTRATIO REPLACE HERE CONVERT

The Image command has other functions (e.g. LOCATE) so you definitely need CONVERT to activate the image conversion function.

Thank you, guys.
Once again, I'm blown away by how fast you get the questions answered here...