It does exist, because older PGP were mandated (by RFC 4880) to use SHA1. Other implementations can coexist with different digest functions, though, so read on...
We've known for a while that reliance on SHA1 was problematic - see the top of src/crypto/external/bsd/netpgp/dist/src/netpgp/netpgp.c where the default for new netpgp-signatures is sha256:
/*
* SHA1 is now looking as though it should not be used. Let's
* pre-empt this by specifying SHA256 - gpg interoperates just fine
* with SHA256 - agc, 20090522
*/
#define DEFAULT_HASH_ALG "SHA256"
I'm aware of the dangers of downgrading various things, though not PGP? Quite happy to panic if warranted