diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6c07596..31dcaf2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -459,8 +459,10 @@ endif(CYGWIN OR NOT WIN32)
 
 # PLplot MANDATORY
 # -DPLPLOTDIR=DIR
-set(CMAKE_PREFIX_PATH ${PLPLOTDIR})
-find_package(Plplot QUIET)
+
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(PLPLOT REQUIRED plplot plplot-c++)
+
 set(HAVE_LIBPLPLOTCXXD ${PLPLOT_FOUND})
 if(PLPLOT_FOUND)
     set(LIBRARIES ${LIBRARIES} ${PLPLOT_LIBRARIES})
@@ -635,33 +637,16 @@ endif(GRAPHICSMAGICK_FOUND)
 # -DMAGICK=ON|OFF
 # -DMAGICKDIR=DIR
 if(MAGICK)
-  set(CMAKE_PREFIX_PATH ${MAGICKDIR})
-  find_package(ImageMagick QUIET COMPONENTS Magick++ MagickWand MagickCore)
-  mark_as_advanced(ImageMagick_EXECUTABLE_DIR ImageMagick_Magick++_INCLUDE_DIR ImageMagick_Magick++_LIBRARY
-    ImageMagick_MagickCore_INCLUDE_DIR ImageMagick_MagickCore_LIBRARY ImageMagick_MagickWand_INCLUDE_DIR ImageMagick_MagickWand_LIBRARY)
-  set(USE_MAGICK ${ImageMagick_FOUND})
-  if(ImageMagick_FOUND)
-    find_program(MAGICKXXCONFIG Magick++-config)
-    if(MAGICKXXCONFIG)
-      execute_process(COMMAND ${MAGICKXXCONFIG} "--libs" OUTPUT_VARIABLE MAGICKXXCONFIGLIBS OUTPUT_STRIP_TRAILING_WHITESPACE)
-      set(LIBRARIES ${LIBRARIES} ${MAGICKXXCONFIGLIBS})     
-    else(MAGICKXXCONFIG)
-      message(FATAL_ERROR "ImageMagick is required but was not found (Magick++-config).\n"
-    "Use -DMAGICKDIR=DIR to specify the ImageMagick directory.\n"
-    "Use -DMAGICK=OFF to not use it.\n"
-        "(suitable Debian/Ubuntu package: libmagick++-dev)\n"
-        "(suitable Fedora/CentOS package: ImageMagick-c++-devel)")
-    endif(MAGICKXXCONFIG)
-    set(LIBRARIES ${LIBRARIES} ${ImageMagick_LIBRARIES})
-    include_directories(${ImageMagick_INCLUDE_DIRS})
-    set(MAGICK_LIBRARIES ${ImageMagick_LIBRARIES})
-  else(ImageMagick_FOUND)
-    message(FATAL_ERROR "ImageMagick is required but was not found.\n"
-      "Use -DMAGICKDIR=DIR to specify the ImageMagick directory.\n"
-      "Use -DMAGICK=OFF to not use it.\n"
-      "(suitable Debian/Ubuntu package: libmagick++-dev)\n"
-      "(suitable Fedora/CentOS package: ImageMagick-c++-devel)")
-  endif(ImageMagick_FOUND)
+  find_package(PkgConfig REQUIRED)
+  pkg_check_modules(Magick++ REQUIRED Magick++)
+  pkg_check_modules(MagickWand REQUIRED MagickWand)
+  pkg_check_modules(MagickCore REQUIRED MagickCore)
+
+  set(MAGICK_LIBRARIES ${Magick++_LIBRARIES} ${MagickWand_LIBRARIES} ${MagickCore_LIBRARIES})
+  set(LIBRARIES ${LIBRARIES} ${MAGICK_LIBRARIES})
+  include_directories(${Magick++_INCLUDE_DIRS})
+  include_directories(${MagickWand_INCLUDE_DIRS})
+  include_directories(${MagickCore_INCLUDE_DIRS})
 endif(MAGICK)
 
 ## not valid anymore I bet ## if GM or IM activated, we check whether Plplot is OK for that
@@ -1037,20 +1022,8 @@ endif(GLPK)
 # -DSHAPELIB=ON|OFF
 # -DSHAPELIBDIR=DIR
 if(SHAPELIB)
-  set(CMAKE_PREFIX_PATH ${SHAPELIBDIR})
-  find_package(SHAPELIB QUIET)
-  set(USE_SHAPELIB ${SHAPELIB_FOUND})
-  if(SHAPELIB_FOUND)
-    set(LIBRARIES ${LIBRARIES} ${SHAPELIB_LIBRARIES})
-    include_directories(${SHAPELIB_INCLUDE_DIR})
-  else(SHAPELIB_FOUND)
-    message(FATAL_ERROR "SHAPELIB (http://shapelib.maptools.org/)  is required but was not found.\n"
-      "Use -DSHAPELIBDIR=DIR to specify the SHAPELIB-devel directory tree.\n"
-      "Use -DSHAPELIB=OFF to not use it.\n"
-      "shapelib is often in package libshp-devel.\n"
-      "(suitable Debian/Ubuntu package: libshp-dev)\n"
-      "(suitable Fedora/CentOS package: shapelib-devel)\n")
-  endif(SHAPELIB_FOUND)
+  find_package(PkgConfig REQUIRED)
+  pkg_check_modules(shapelib REQUIRED shapelib)
 endif(SHAPELIB)
 # EXPAT for IDLffXMLSAX and IDLffXMLDOM
 # -DEXPAT=ON|OFF
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index f1923d2..6f1343e 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -193,9 +193,9 @@ ${WX_RC}
 )
 endif(HAVE_LIBWXWIDGETS AND WIN32)
 
-add_subdirectory(antlr)
+find_library(ANTLR_LIBRARY NAMES antlr)
 
-include_directories(${CMAKE_SOURCE_DIR} ${CMAKE_SOURCE_DIR}/src ${CMAKE_SOURCE_DIR}/src/antlr ${CMAKE_BINARY_DIR})
+include_directories(${CMAKE_SOURCE_DIR} ${CMAKE_SOURCE_DIR}/src ${CMAKE_BINARY_DIR})
 link_directories(${LINK_DIRECTORIES})
 
 if(PYTHON_MODULE) #GDL.so
@@ -213,8 +213,7 @@ if(USE_OPENMP)
 	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
 endif(USE_OPENMP)
 
-add_dependencies(gdl antlr) # be sure that antlr is built before gdl
-target_link_libraries(gdl antlr) # link antlr against gdl
+target_link_libraries(gdl ${ANTLR_LIBRARY}) # link antlr against gdl
 if (MINGW)
 target_link_libraries(gdl ws2_32)
 endif (MINGW)