Section 1.1.1 says:

   1.1.1. Two RRs are considered equal if their NAME, CLASS, TYPE,
   RDLENGTH and RDATA fields are equal.  Note that the time-to-live
   (TTL) field is explicitly excluded from the comparison.
It should say:

   1.1.1. Two RRs are considered equal if their NAME, CLASS, TYPE,
   RDLENGTH and RDATA fields are equal.  Compressed names in the RDATA
   must be decompressed before comparison. Note that the time-to-live
   (TTL) field is explicitly excluded from the comparison.