All authentication fails when auth schema version 4 used with SCRAM as only mechanism

Encountered against Amazon SSL 64-bit 2.7.7-pre build from this morning. (at commit 986d4a410e).

When authSchemaVersion=4 is used together with --setParameter authenticationMechanisms=SCRAM-SHA-1, authentication on the shell always fails, even when explicitly specifying the mechanism.

For example:

> use admin

> db.auth({user:"admin", pwd:"foo", mechanism:"SCRAM-SHA-1"})

Error: 18 Authentication failed.

0

The server log contains the following message on each failed attempt when specifying the mechanism:

2014-09-19T20:36:57.602+0000 I ACCESS   [conn4] SCRAM-SHA-1 authentication failed for admin on admin ; BadValue Illegal value for authorization data schema version, 4