This is the package signature as generated by The GnuPG. This signature identifies the party that created the package. By verifying it you are sure that the package coming from a trustworty person or organization.
Here is the package signature:
-----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkkgPt0ACgkQqesEzEdeXBHHMwCfStqcBdJN7W/xkaNwJsQt0zoN uzkAn28BbVtCYGd87Sum2NFYu9dx5boH =6XOi -----END PGP SIGNATURE-----
You can save this signature in a text file (e.g. libmpcdec-1.2.6-i486-2gds.tgz.asc) in the same directory where the package file (libmpcdec-1.2.6-i486-2gds.tgz) resides and you can verify it by issuing the following command:
gpg --verify libmpcdec-1.2.6-i486-2gds.tgz.asc
NOTE: You need to import the public key of SlackPack first:
gpg --import KEY