When triggering a UBE filter to run an external batch file, it doesn't work, although the rule is triggered.

Question

UBE filters are not running a batch file as
an external program. The batch file is located in the postoffice spool
directory and has the correct permissions.
<P>
Change the RUN command to REJECT to check that it was actually triggered.
<P>
<B>Background:</B>
<P>
Example:
<P>
filter.cfg is as follows:
<P>
:Test Channel-To "ecxpert@host\.domain\.com" RUN "test.bat"<BR>
:sendback Channel-To "ecxpert@host\.domain\.com" COPY "pvtest1@host\.domain\.com"
<P>
filter.opt is as follows:
<P>
# To parse header fields as well as envelope fields remove the comment (#) from the following<BR>
# line. See Help for more information<BR>
parseheader:1
<P>
test.bat resides in C:\Netscape\Suitespot\MailServer\Spool and is as follows:
<P>
date /t >> test.txt
<P>
This would be 100% correct for any Unix system, with the addition of a top line
to the script determining what shell to use. However, with NT, shell type
definition is not part of a batch file.
Correcting the UBE filter in filter.cfg to read as follows cures the problem:
<P>
:Test Channel-To "ecxpert@host\.domain\.com" RUN "cmd.exe /c test.bat"
<BR>
:sendback Channel-To "ecxpert@host\.domain\.com" COPY "pvtest1@host\.domain\.com"
<P>
The following also works:
<P>
:Test Channel-To "ecxpert@host\.domain\.com" RUN "cmd.exe /c date /t test.txt"<BR>
:sendback Channel-To "ecxpert@host\.domain\.com" COPY "pvtest1@host\.domain\.com"
<P>
The reasoning behind this is that batch files are scripts for CMD.EXE, the
NT Shell, and therefore cannot be executed directly. CMD.EXE has the /C
switch to run a following command, or batch file, and exit on completion.
<P>
Another solution would be to write an executable program in BASIC or any
other chosen language to perform the same functions. However, do compile it to an
executable before trying to use it since, for example, a *.BAS file will
run in Windows but it means nothing to Messaging Server.

Answer 1

Look at the documentation of Runtime.exec()
There are versions of that method that allow you to specify the name of an executable (the name of your batch file) and also an array of strings with environment parameters. I've never used this myself, but it should work like this (lookup the documentation!):
Runtime.getRuntime().exec("bla.bat", new String[] { "ROOTDIR=" + rootdir });