When running create.product.zip from Hudson/Buckminster job, the ${repository} value that gets passed from buckminster to the ant
create.product.zip task gets converted to a URI prior to the task call, and then seemingly additionally URLEncoded by something on the ant side.
If the value is a path containing spaces, this results in "%2520" character (which is %20, i.e. a URLEncoded space, URLEncoded again).

hudson command-line call output:
[code]
Commandline:
java -Dbuckminster.output.root=D:\Data\Java Builds\Hudson\jobs\My Manager RCP build\workspace\buckminster.output -
Dbuckminster.temp.root=D:\Data\Java Builds\Hudson\jobs\My Manager RCP build\workspace\buckminster.temp -jar
plugins\org.eclipse.equinox.launcher_1.0.200.v20090520.jar -application org.eclipse.buckminster.cmdline.headless -data D:\Data\Java
Builds\Hudson\jobs\My Manager RCP build\workspace -loglevel debug -S D:\Data\Java Builds\Hudson\jobs\My Manager RCP build\builds\2009-09-23_20
54-57\commands.txt setpref 'targetPlatformPath=D:\Data\Java Builds\Hudson\jobs\My Manager RCP Platform creation\builds\2009-09-22_11-15-
18\archive\targetPlatform'
targetPlatformPath set to the value 'D:\Data\Java Builds\Hudson\jobs\My Manager RCP Platform creation\builds\2009-09-22_11-15-
18\archive\targetPlatform'
[/code]

buckminster output:

[code]
!SESSION 2009-09-23 17:37:30.213 -----------------------------------------------
eclipse.buildId=unknown
java.version=1.6.0_13
java.vendor=Sun Microsystems Inc.
BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=en_US
Framework arguments: -application org.eclipse.equinox.p2.director -artifactRepository
file:file:/D:/Data/Java%20Builds/Hudson/jobs/My%20Manager%20RCP%20build/workspace/buckminster.output/arc.manager.feature_1.0.0-
eclipse.feature/site.p2/ -metadataRepository
file:file:/D:/Data/Java%20Builds/Hudson/jobs/My%20Manager%20RCP%20build/workspace/buckminster.output/arc.manager.feature_1.0.0-
eclipse.feature/site.p2/ destination D:\Data\Java Builds\Hudson\jobs\My App RCP build\workspace\buckminster.output\arc.manager.feature_1.0.0
eclipse.feature\MyManagerApp -bundlepool D:\Data\Java Builds\Hudson\jobs\My App RCP
build\workspace\buckminster.output\arc.manager.feature_1.0.0-eclipse.feature\MyManagerApp -profile MyManagerProfile -profileProperties
org.eclipse.update.install.features=true -installIU arc.manager.product -p2.os win32 -p2.ws win32 -p2.arch x86
Command-line arguments: -application org.eclipse.equinox.p2.director -artifactRepository
file:file:/D:/Data/Java%20Builds/Hudson/jobs/My%20Manager%20RCP%20build/workspace/buckminster.output/arc.manager.feature_1.0.0-
eclipse.feature/site.p2/ -metadataRepository
file:file:/D:/Data/Java%20Builds/Hudson/jobs/My%20Manager%20RCP%20build/workspace/buckminster.output/arc.manager.feature_1.0.0-
eclipse.feature/site.p2/ destination D:\Data\Java Builds\Hudson\jobs\My App RCP build\workspace\buckminster.output\arc.manager.feature_1.0.0
eclipse.feature\MyManagerApp -bundlepool D:\Data\Java Builds\Hudson\jobs\My App RCP
build\workspace\buckminster.output\arc.manager.feature_1.0.0-eclipse.feature\MyManagerApp -profile MyManagerProfile -profileProperties
org.eclipse.update.install.features=true -installIU arc.manager.product -p2.os win32 -p2.ws win32 -p2.arch x86 -consoleLog

!ENTRY org.eclipse.equinox.p2.artifact.repository 4 1000 2009-09-23 17:37:31.791
!MESSAGE No repository found at
file:/D:/Data/Java%2520Builds/Hudson/jobs/My%2520Manager%2520RCP%2520build/workspace/buckminster.output/my.manager.feature_1.0.0-
eclipse.feature/site.p2/.

!ENTRY org.eclipse.equinox.p2.core 4 0 2009-09-23 17:37:31.806
!MESSAGE Unable to load repositories.
[/code]