Unfortunately, you can't use an address in replace of a pubkey.
An address is a one way hash of a pubkey. Its not possible to use an address because it cant be used to generate a pubkey, and its the pubkeys (which is included in the redeem scripts) that are needed to validate the signatures in a transaction when you release/send the coins from your mutlsig address.
I'm talking about compressed
public key, not address.
latest bitcoin-qt client seems only generate address from compressed public key.
so all my addresses are associated with compressed publickey (prefix with 02/03, not 04).
and when compressed publickeys are used, their private keys also in different format, (prfix with K/L instead of 5)
there will be a compatible issue if your apps only support uncompressed pkey.