No, haven't heard of it.. I have tried pineapple for colds.. I haven't noticed/discerned much of a effect.. but I recommend you try anyway..

These are the effects I'm aware of..

vitamin c or orange/orange juice when you have a cold.. I have seen it in me.. stop a runny nose in under a hour.. and just plug it up..

I have noticed that a shower (really hot water/steam in the air does it) or chicken soup loosens the throat makes you feel good during a cold..

I have sometimes seen "lemonade" make my colds feel better.. as mentioned in my cold thread.. it was suggested the acid is helpful..

(these are the only effects I'm aware off.. as far as I know the chicken soup/shower is probably the only reproducible one in people.. both vitamin c and lemonade maybe iffy.. it was also suggested to me that it takes calcium to get vitamin c to digest so there's something else to consider)