2 files changed, 37 insertions, 12 deletions

diff --git a/configure.ac b/configure.ac
index 4e0c4ba..fa1de7a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -7,14 +7,38 @@ AC_CONFIG_FILES([
         src/Makefile
 ])
 
+##################
+# MODULE: OpenGL #
+##################
+
+# Note that this project will not build on systems where the OpenGL
+# support libraries do not include support for buffer objects.
+
 # Check for OpenGL libraries GLUT, GLU and GL.  OpenGL is used for the
 # visualization rendering and interaction.
 AX_CHECK_GLUT
 
-# Check for DB2.
-AC_SEARCH_LIBS([sqlastrt],[db2])
+###############
+# MODULE: DB2 #
+###############
+
+# Check for DB2 client library.
+AC_SEARCH_LIBS([sqlastrt],[db2],[],
+[AC_MSG_ERROR(The DB2 client libraries are needed to build the system. After installation of the client it may be necessary to add -L/home/db2inst1/sqllib/lib to LDFLAGS.)])
+
+# Check for DB2 client headers.
+AC_CHECK_HEADERS([sqladef.h],[],
+[AC_MSG_ERROR(The DB2 client headers are needed to build the system. After installation of the client it may be necessary to add -I/home/db2inst1/sqllib/include to CPPFLAGS.)])
+
+##########################
+# MODULE: BROWSER PLUGIN #
+##########################
 
 # Libtool is used to build the library for the browser plugin.
 AC_PROG_LIBTOOL
 
+# Check for the Gecko Plugin API
+AC_CHECK_HEADERS([npapi.h],[],
+[AC_MSG_ERROR(The Gecko Plugin API (NPAPI) is needed to build the system. Information on this API can be found on-line at https://developer.mozilla.org/en/Plugins. Debian users can add the package xulrunner-dev and add -I/usr/include/xulrunner-1.9/unstable to CPPFLAGS.)])
+
 AC_OUTPUT