I am looking to convert a pktt file so as to look at it using snoop utility supplied with Solaris.
Editcap, which comes with Ethereal:
can convert tcpdump-format files (which is what pktt files are) into snoop files, or vice versa; it can also convert between a number of other file formats.
Of course, Ethereal itself can read tcpdump-format capture files and snoop captue files, as well as all the formats Editcap can use (as they use the same code to read capture files), as can the snoop-like Tethereal. And the current version of Ethereal can reassemble fragmented IP datagrams, as well as NFS (and other RPC)-over-TCP requests and replies, SMB/CIFS requests and replies, and DNS-over-TCP requests and replies that are split across TCP segment boundaries (unlike snoop, unless they've improved it recently...).
(It's "ethereal.com" solely because "ethereal.org" was already taken; Ethereal isn't commercial software, it's GPLed free software.)
I was also provided with the same file converted into a sniffer pro file, however, my sniffer box is not accessible at the moment.
Ethereal should also be able to read many Sniffer and Sniffer Pro files (as should Editcap).