I wanted to use a google maps latlng to pinpoint the meeting place for an outdoor event. The url I used was this:
http://maps.google.com/maps?t=100m&q=loc:50.88173,+-0.0082
This URL works in a browser (you can try it) but e-Voice doesn't consider it to be a valid URL.
Change the WYSIWYG editor to HTML and paste in the code where you want it