I'm not sure if anyone else has been watching this closely, but the next version of GnuPG looks set to support DSA2 keys. SVN compiles of the system already allow the use of DSA2 signing with existing DSA keys, and have lately also support the generation of new DSA2 keys.
DSA2 keys are a new type of DSA key that move beyond the 1024-bit key size and the 160-bit hash limit of the original DSA1 keys. DSA2 keys form part of a new (forthcoming) OpenPGP standard.
DSA2 keys have their hash size hardcoded into them. This size cannot be changed once the key is generated. The hash you use when signing must be as large or greater than the hash size hardcoded into the key. If your DSA2 is generated with a 256-bit hash size you cannot use 160bit SHA1 signing. However, you can use a hash size larger than the one hardcoded into the key, and it will be truncated to fit.
The current key size/hash sizes are as follows:
* 160 bits of hash for a key with 1024 bits of encryption (same as DSA1)
* 224 bits of hash for a key with 1024 to 2048 bits of encryption
* 256 bits of hash for a key with 2048 to 3072 bits of encryption
This is useful as it means that existing DSA keys relying on SHA1 signing are being given a new lease of life.