vsbuild target command works on v17 but v18 I get this error

[DanW]

CallTarget -t "vsbuild"
---------- 'vsbuild' Project: 'images\vxworks\ic_vxworks.vpj' - 'Release' ---------- VSLICKERRORPATH="F:\workspace\sw\product\SF260-HLD\develop\app\ic\images\vxworks\%rp"
vsbuild command can't change workspace, project, config, or target. Use CallTarget


and here the section in the project file:
         <Target
            Name="vsbuild"
            MenuCaption="&amp;vsbuild"
            RunFromDir="%rp"
            ShowOnMenu="Never"
            CaptureOutputWith="ProcessBuffer">
            <Exec CmdLine='"%(VSLICKBIN1)vsbuild" make "%w" "%r" -cppmake'/>
         </Target>
         <Target
            Name="vsrebuild"
            MenuCaption="&amp;vsrebuild"
            ShowOnMenu="Never"
            CaptureOutputWith="ProcessBuffer"
            RunFromDir="%rp">
            <Exec CmdLine='"%(VSLICKBIN1)vsbuild" rebuild "%w" "%r" -cpprebuild'/>
         </Target>

whereas, v17 did this when compiling the vsbuild and rebuild commands: (note it did not add %rp to the end of the path)
VSLICKERRORPATH="f:\workspace\sw\product\SF260-HLD\develop\app\ic\images\vxworks"
cd ..\..\..\..
cd app\common\messaging
make -f Makefile all