views with non-numeric pager IDs break ajax

to reproduce:

• create a paged view with a block display - leave the Pager ID at the default value.
• enable ajax on the view and place the block into a homebox display
• the pager should work fine
• edit the view and change the pager ID to something like "page_one". views accepts this as a valid value.
• revisit the homebox display and test the pager. the throbber pops up but the pages don't advance.

pretty easy to work around - just stick with numeric pager IDs. however it was a surprise for me when plopping some pre-built views into a display.