Site Maintenance gives confusing status message

Drupal 5.7: When moving a site from a Site Maintenance = Off-line state to a Site Maintenance = Online state, a confusing status message is displayed.

From an off-line state [See attachment: SiteMaintenance-Offline.png ], toggling the site to Online and clicking Save Configuration, results in the following status messages being displayed:

    * Operating in off-line mode.
    * The configuration options have been saved.

The first message, incorrectly indicates that the site is still in "off-line" mode even though it is actually in online mode. [See attachment: SiteMaintenance-OfflineToOnline.png ]

If the user then clicks Save Configuration again, the following status message is displayed:

    * The configuration options have been saved.

[See attachment: SiteMaintenance-Online-ConfigurationOptionsSave.png ]

The status message, while in an online state, should never indicate that the site is off-line.