In case if someone wants this, I changed line 229 in ui.c:
tmp = g_strdup_printf("%02d:%02d:%02d", tm->tm_hour, tm->tm_min, tm->tm_sec);
to:
tmp = g_strdup_printf("%d:%02d", tm->tm_hour, tm->tm_min);
It corresponds to format "h:mm".
In case if someone wants this, I changed line 229 in ui.c:
tmp = g_strdup_ printf( "%02d:% 02d:%02d" , tm->tm_hour, tm->tm_min, tm->tm_sec);
to:
tmp = g_strdup_ printf( "%d:%02d" , tm->tm_hour, tm->tm_min);
It corresponds to format "h:mm".