This has been plaguing me for awhile now. I had to switch from DeLorme to GlobalSat GPS receivers since the serial emulator would not allow external programs to access the GPS stream easily. I am using the perl distro Perl-GPS 0.16 to access the NMEA receiver. Using this small program:

 #!/usr/bin/perl
#perl2exe_include "bytes.pm" 

    use GPS::NMEA;
    use Data::Dumper;
    
    my $gps = GPS::NMEA->new(Port => 'COM6', # or COM5: or /dev/ttyS0
                             Baud => 4800);
    while(1) {
        $gps->parse;
    
        # Dump internal NMEA data:
        $gps->nmea_data_dump;
    
        # Alternative to look at the internal NMEA data:
        require Data::Dumper;
        print Data::Dumper->new([$gps->{NMEADATA}],[])->Indent(1)->Use
+qq(1)->Dump;
    }
    __END__
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I have received this error:

Second Read attempted before First is done at C:/Perl/site/lib/GPS/Ser
+ial.pm lin
e 55
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which sounds like it could be a baud problem but I have tried it with several other values and received the same error.