I was able to transcribe this much from a couple of sound samples at Yahoo! Music. I failed to find any lyrics on the web, though, which is usually the case for Jansch songs.

...jingling and sweetly does it call.
Oh ring-a-ding
Oh ring-a-ding
Oh ring-a-ding bird, sing your song for me.

Hey, little bird,
I walk beneath the trees
And I see an ageless man
Who plays a timeless tune
Upon a golden banjo
And he sings a song of laughter
And sadness....