They won't work, you have to buy P2 cards for those cameras.
No idea what adapter you are talking about but even if there is one that converts the SDHC cards to a PCMCIA form factor, it would still not be P2 compatible.
FWIW - a P2 card has (4) SD cards that are RAIDed (is that a word?) together to give the record speed needed for handling the data rates of the HD formates. HDV cameras can get away with the small cards because HDV data rate is less the standard DV data rates, a 1/4 of DVCProHD.
Yeah there are PCMCIA to SDHC card readers but that's a whole other universe from a card that somehow makes SDHC into P2. I'd love to have one but I've never ever heard or seen one and doubt one will ever exist with Panasonic's proprietary ownership of the P2 technology.