Here goes:
Server is Windows NT. Seems to work on an alternative XP installation although the default it picked up might have matched the one I wanted - have been playing around porting project files from beetlejuice so can't get you the working data at present. I'll get these on here as soon as I get them
Server's JAVA_HOME is c:\java\j2sdk1.4.2_05
Registered JDK within bamboo is c:\java\j2sdk1.4.2_05
Jdk being used for ant build is C:\Program Files\Java\jdk1.5.0_06\bin\javac.exe
administration.xml is:
<AdministrationConfiguration>
<myBaseUrl>http://lonw015573.uk.net.intra:8085</myBaseUrl>
<myDataFormatVersion>2</myDataFormatVersion>
<myBuildDirectory>D:\Bamboo\Bamboo\xml-data\build-dir</myBuildDirectory>
<myRepositoryPollingPeriod>120</myRepositoryPollingPeriod>
<myUseGzipCompression>false</myUseGzipCompression>
<myJdks>
<entry>
<string>1.4.2</string>
<JdkPathMap>
<myLabel>1.4.2</myLabel>
<myHomeDirectory>c:\java\j2sdk1.4.2_05</myHomeDirectory>
</JdkPathMap>
</entry>
</myJdks>
<myLicense>SETUP-COMPLETE</myLicense>
<myEnableRemoteApi>false</myEnableRemoteApi>
<myBuilderLabelPathMaps>
<entry>
<string>Ant 1.6.2</string>
<LabelPathMap>
<myLabel>Ant 1.6.2</myLabel>
<myHomeDirectory>d:\utilities\apache-ant-1.6.2</myHomeDirectory>
<myBuilderType>com.atlassian.bamboo.plugin.system.builder:ant</myBuilderType>
</LabelPathMap>
</entry>
</myBuilderLabelPathMaps>
</AdministrationConfiguration>
After a few server start/stops it still does it. Having done a text search (limited by windows' own search facility) the only reference to that jdk i can find is in the buildresults xml files.
turns out ant is being set to use it in a build properties file from our project, so it's our build screwing up, not yours. ta, think you can close this one fully now.