Patch by Robert Scheck <robert@fedoraproject.org> for zarafa >= 6.40.0, which adds
some more flexibility to detect CLucene headers and libraries. Right now, Zarafa is
linking static to CLucene, which is a no-go at Fedora. That means CLucene on Fedora
doesn't provide static library files at all. To keep Zarafa's behaviour for their
own builds, the patch looks for "libclucene.a" and links static; otherwise (Fedora)
it links dynamically using -lclucene. More details about static linking and Fedora:
http://fedoraproject.org/wiki/Packaging:Guidelines#Packaging_Static_Libraries

Zarafa's internal CLucene build for Zarafa seems to violate upstream's decision, as
CLucene upstream decided with 0.9.20 release to put "CLucene/clucene-config.h" file
into /usr/lib{,64}/CLucene/clucene-config.h because of arch-specific values. Fedora
is shipping CLucene using upstream's decision, thus ./configure needs to handle the
include path with GCC CPP, too. To avoid CPP telling "rejected by the preprocessor"
as of the missing include path (/usr/include is standard, but /usr/lib{,64} isn't),
$CXXCPP needs to be temporarily extended to contain this special path as well.

--- zarafa-6.40.0/configure.ac			2010-06-06 14:47:37.000000000 +0200
+++ zarafa-6.40.0/configure.ac.clucene		2010-06-06 15:16:18.000000000 +0200
@@ -394,17 +394,26 @@
   [CLUCENE_INCLUDE_PREFIX=${withval}],[CLUCENE_INCLUDE_PREFIX=/usr/include])
 cflags_keep=$CFLAGS
 cxxflags_keep=$CXXFLAGS
+cxxcpp_keep=$CXXCPP
 if test "x$CLUCENE_LIB_PREFIX" != "x"; then
    CFLAGS="$CFLAGS -I$CLUCENE_LIB_PREFIX"
    CXXFLAGS="$CFLAGS -I$CLUCENE_LIB_PREFIX"
+   CXXCPP="$CXXCPP -I$CLUCENE_LIB_PREFIX"
 fi
 if test "x$CLUCENE_INCLUDE_PREFIX" != "x"; then
    CFLAGS="$CFLAGS -I$CLUCENE_INCLUDE_PREFIX"
    CXXFLAGS="$CFLAGS -I$CLUCENE_INCLUDE_PREFIX"
+   CXXCPP="$CXXCPP -I$CLUCENE_INCLUDE_PREFIX"
+fi
+if test -e "${CLUCENE_LIB_PREFIX}/libclucene.a"; then
+  AC_CHECK_LIB(clucene, [open],
+    [ CLUCENE_LIBS="${CLUCENE_LIB_PREFIX}/libclucene.a" ],
+    [ WITH_CLUCENE=no ])
+else
+  AC_CHECK_LIB(clucene, [open],
+    [ CLUCENE_LIBS="-lclucene" ],
+    [ WITH_CLUCENE=no ])
 fi
-AC_CHECK_LIB(clucene, [open],
-  [ CLUCENE_LIBS="${CLUCENE_LIB_PREFIX}/libclucene.a" ],
-  [ WITH_CLUCENE=no ])
 AC_CHECK_HEADERS([CLucene.h],
   [ CLUCENE_CFLAGS="-DLUCENE_DISABLE_MEMTRACKING" ],
   [ WITH_CLUCENE=no ])
@@ -419,6 +428,7 @@
 AC_SUBST(CLUCENE_LIBS)
 CFLAGS=$cflags_keep
 CXXFLAGS=$cxxflags_keep
+CXXCPP=$cxxcpp_keep
 AC_LANG_POP
 
 # Check for google perftools tcmalloc availability