Javac problem

[ERICWEI]

I have what may be a very stupid question, because I have been using ant for only a 
couple hours now. But here we go:

here is a portion of my simple.xml file being used by ant:

[other targets and init]

<target name="prepare" depends="clean"> 
<mkdir dir="${outputDir}" /> 
<mkdir dir="${zipDir}" />
</target> 

<target name="print1" depends="prepare">
<echo message="this is test1"/>
</target>

<target name="compile" depends="print1"> 
<javac srcdir="${sourceDir}" destdir="${outputDir}" deprecation="off"/> 
</target>

<target name="zip" depends="compile">
<zip zipfile="${zipDir}/joel.zip" basedir="${vssDir}"/>
</target>

<target name="print2">
<echo message="test2"/>
</target> 

the zip never gets reached. here is the output:

clean:
  [deltree] DEPRECATED - The deltree task is deprecated.  Use delete instead.
  [deltree] Deleting: C:\WebApps\backoffice\web-inf
  [deltree] DEPRECATED - The deltree task is deprecated.  Use delete instead.

prepare:
    [mkdir] Created dir: C:\WebApps\backoffice\web-inf
    [mkdir] Created dir: C:\WebApps\backoffice\zip

print1:
this is test1

compile:
    [javac] Compiling 1 source file to C:\WebApps\backoffice\web-inf

BUILD SUCCESSFUL

i have no clue why the zip never runs. any help would be greatly appreciated.

thanks,
eric