Show Month on Manage->Posts shows blank title

[ryanscheuermann]

Fresh install, trunk code. Click Manage->Posts, then click "Show Month" for any month. The page title changes from "Last 15 Posts" to blank.

[Viper007Bond]

single_month_title() is returning an empty string: string(0) ""

Not familiar with the function, so I'll leave it up to someone else to figure out why it's not working.

[markjaquith]

(In [4346]) fix usage of $m and return behavior in single_month_title(). fixes #3207