In some of the rpms the gid of the user building is used instead of 0.
From the syslog-ng rpm:
drwxr-xr-x    2 root    gsa                         0 Apr  7  2012
/usr/share/include/scl/pacct
-rw-r--r--    1 root    gsa                      1236 Sep 15  2011
/usr/share/include/scl/pacct/plugin.conf
drwxr-xr-x    2 root    gsa                         0 Apr  7  2012
/usr/share/include/scl/syslogconf
-rw-r--r--    1 root    gsa                       264 Dec 31  2010
/usr/share/include/scl/syslogconf/README
-rwxr-xr-x    1 root    gsa                      3664 Dec 31  2010
/usr/share/include/scl/syslogconf/convert-syslogconf.awk
-rw-r--r--    1 root    gsa                      1181 Sep 15  2011
/usr/share/include/scl/syslogconf/plugin.conf
drwxr-xr-x    2 root    gsa                         0 Apr  7  2012
/usr/share/include/scl/system
-rwxr-xr-x    1 root    gsa                      3355 Sep 15  2011
/usr/share/include/scl/system/generate-system-source.sh
-rw-r--r--    1 root    gsa                      1159 Sep 15  2011
/usr/share/include/scl/system/plugin.conf
Note: gsa is 1000 in our rootfs, and the user building i rootfs primary group is also 1000.
We also see this problem in our own bb files if we use 'cp -a'. We need to use 'cp -a --no-preserve=ownership' to get around this problem.
Example of bb file workaround:
 do_install() {
        install -d -m 0755 ${D}/opt/java
-       cp -a ${S}/usr/java/${JDK_JRE}${PV}_${PV_UPDATE}/ ${D}/opt/java
+       cp -a --no-preserve=ownership
${S}/usr/java/${JDK_JRE}${PV}_${PV_UPDATE}/ ${D}/opt/java
       ln -sf ${JDK_JRE}${PV}_${PV_UPDATE} ${D}/opt/java/latest  }
Syslog-ng is extra interesting as it only afftects some of the files/dirs (the ones under /usr/share/include/scl/ the resta are root:root).
        
                        Observe group ownership on a target or unpacked rpm/filesystem.