UPDATE:
Poloniex response to my ticket:

Thank you for getting in touch.
Please do not ever send one type of crypto currency to the address of another type of crypto currency. Mistakes like this can lead to the complete and irretrievable loss of your funds and so always be vigilant.
However in this case I am happy to inform you that I have succeeded in recovering the funds for you.
They should be credited to your account shortly.
Please let me know if you feel that there is still an issue.


I confirm that the funda are in my account now.
I'm glad my money isn't lost :-)