The other Marian is in charge of poetry in movies. I tried Google and IMDB, but no luck. I did see a note on the newsgroup alt.quotations where someone speculated it was written for the movie itself:
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tinyurl.com]
"I still remember part of a poem recited by Diana Riggs in the James Bond
movie "On Her Majesty's Secret Service." I've never been able to track it
down and believe it might be invented:
Thy dawn my lord, thy dawn.
For thee it creeps across the lawn,
For thee the flowers bloom and birds fly
For the ******something**** sing "