Why does gdm allow login when an ldap username is preceded with space?

Issue

• Pressing the "space" key to wake the screensaver before entering an LDAP username at the gdm login screen, causes the username and some environmental variables end up as " <username>" instead of "<username>". This only happens on gdm and does not affect text console logins.

• Login is successfull, but environmental variables containing the user's name contain a space before the username.