Gravatar email addresses appear to be case sensitive and therefore don't load properly.

[hotforwords]

Since I added Buddypress to my Wordpress installation, using the Buddypress plugin about 50% of my users lost their Gravatar image and we discovered that it has to do with an old Wordpress bug where the cases had to match between the email address on Gravatar and on the website. So joe@… and Joe@… would not match. Wordpress fixed this bug a while back.

The Gravatar's value is the hexadecimal MD5 hash of the requested users' email address with all whitespace trimmed. And the value is supposed to be case insensitive. (Taken from Wordpress Codex: ​http://codex.wordpress.org/Using_Gravatars) But it appears that Buddypress brings back this bug where the email address is suddenly case-sensitive for Gravatars.

[beaulebens]

Gravatar email addresses *are* case sensitive, and always have been. If you md5 a string with differing cases, it will create a different hash and therefore not resolve properly on Gravatar.

Emails *must* be lowercased before hashing them to request a Gravatar.

$hash = md5( strtolower( $email ) );

[cnorris23]

@hotforwords
I've gone through and added strtolower per beaulebens' comment. Give the patch a test, and make sure everything works.

[johnjamesjacoby]

(In [3026]) Fixes #2391 props cnorris23, beaulebens, alot