Using the time stamp of the passing in combination with the stored value for ref_computer_time and ref_time_stamp we can calculate the true computer time of the passing as follows:

KARLS07;17ca;0151cbf5;26;13;9f;15;0;0;1;00;0

Pseudocode calculating the true computer passing time:

passing_time_epoch = ref_computer_time + ((pass_time_stamp - ref_time_stamp) / 256.0)    

    // passing_time_epoch = 0x4a3caa45 + (0x0151cbf5 - 0x0151bcf5)/256.0
    // ref_computer_time = 0x4a3caa45 => June 20 2009 11:22:14 UTC+2 
    // pass_time_stamp = 0x0151cbf5 => taken from passing data above 
    // ref_time_stamp = 0x0151bcf5 => given in reply to EPOCHREFSET     
    //      => 1245489748

passing_time = epoch_to_datetime(passing_time_epoch)
    // passing_time      => Jun 20 2009, 11:22:29 UTC +2

=> June 20th 2009, 11:22:29 UTC +2