hi kiransmailid and welcome,

what have you tried and where you encounter problems?
you have an HashOfArrays as described in perldsc.
i think you can simply cycle the hash and check for the presence of the element 1 of the array that is the value for that key of the hash.

L*

perl -MData::Dumper -e "  
                          %h = ('Message2' => [ '0X026007' ], 'Message
+4' => [ '0X026005', '0X026006' ] );
                          foreach $k(keys %h) { 
                                  delete $h{$k} if defined $h{$k}[1]  
                          } 
                          print Dumper(\%h)
                       "


$VAR1 = {
          'Message2' => [
                          '0X026007'
                        ]
        };
[download]

UPDATE: in the remote past existed caveats about modifying hashes while iterating over them; we are speaking of Perl release prior 5.8 see Adding or removing keys while iterating over a hash Re: Deleting Hash Entries while Iterating

L*