This particular question has cropped up a few times recently. Basically, Spiros is spot on with his advice. However, I would just suggest one minor change - if I understood you correctly, you wish to use a Trados memory (in .txt format) in Wordfast. If so, do what Spiros said with Olifant, but export it in "Wordfast TM" format (open the memory, click on "File > Export" and choose "Wordfast TM" from the Format drop-down menu). You can then open it in Wordfast (remember to click on the Reorganise button in Wordfast afterwards).
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