[syslog-ng] question on logging templates: strange log lines

[Philipp]

Dear list users

In the near future I would like to migrate from syslog-ng 2 to 3.x. For
this reason I've set up a linux testbox.

Now, I have a problem I lack to see a solution for.

The syslog-ng testing config:

@version:3.0

## GLOBAL
options {
  chain_hostnames(no);
  keep_hostname(yes);
  flush_lines(0);
  stats_freq(3600);
  use_dns(persist_only);
  dns_cache_hosts(/etc/hosts);
};

## SOURCES
source src { unix-stream("/dev/log"); };
source src-kernel { file("/proc/kmsg" program_override("kernel: ")); };
source src-syslog-ng { internal(); };

## LOGGING TEMPLATES
template t_filetmpl { template("$DATE $FACILITY.$PRIORITY $FULLHOST
$MSGHDR$MSG\n"); template_escape(no); };

## DESTINATIONS
destination local4 { file("/var/log/local4.log" template(t_filetmpl)); };

## FILTERS
filter f_local4 { facility(local4); };

## LOGS
log { source(src); filter(f_local4); destination(local4); };


For testing I use the logger command: ` logger -p local4.info -t test
testnachricht2`. This configuration causes, and I do not see why, lines
like these in the /var/log/local4.log file.
[empty line]
testnachricht2 test:  donald.info local4Feb 11 14:26:01Feb 11 14:26:01
local4.info donald test: testnachricht2


However, if I replace the line below "## DESTINATIONS" with
destination local4 { file("/var/log/local4.log" template("$DATE
$FACILITY.$PRIORITY $FULLHOST $MSGHDR$MSG\n")); };

all is perfect. The logged line looks like this:
Feb 11 14:30:22 local4.info donald test: testnachricht2


Please could you tell me what I've missed?

Thanks in advance,
Philipp