For those who aren't PHP enabled, but who could use something like
Brad Choate's MT-Macros plugin, there's another way...
You'd define a bunch of macros thusly
CODE
<MTMacroDefine name="matins1" string="::00::">
Matins
</MTMacroDefine>
<MTMacroDefine name="matins2" string="::01::">
Matins
</MTMacroDefine>
<MTMacroDefine name="matins3" string="::02::">
Matins
</MTMacroDefine>
<MTMacroDefine name="Lauds1" string="::03::">
Lauds
</MTMacroDefine>
<MTMacroDefine name="Lauds2" string="::04::">
Lauds
</MTMacroDefine>
<MTMacroDefine name="Lauds3" string="::05::">
Lauds
</MTMacroDefine>
<MTMacroDefine name="Prime1" string="::06::">
Prime
</MTMacroDefine>
Then in your body, you'd use
CODE
<MTMacroApply>::<$MTEntryDate format="%H"$>::</MTMacroApply>
MT will make the 'date' ::03:: for this post, and the macro will change it to 'Matins'.
Notes: Obviously it needs to be extended through the rest of Prime, Terce, Sext, None, Vespers, and Compline. Also someone with a better grasp of regular expressions than I have could easily make it so that the entries don't triple up...