Fixing BOOST detection

m4/ax_boost_iostreams.m4

@@ -103,10 +103,12 @@ AC_DEFUN([AX_BOOST_IOSTREAMS],
 
             fi
             if test "x$ax_lib" = "x"; then
-                AC_MSG_ERROR(Could not find a version of the library!)
+                echo "Could not find a version of the library!"
+                exit 202
             fi
 			if test "x$link_iostreams" != "xyes"; then
-				AC_MSG_ERROR(Could not link against $ax_lib !)
+				echo "Could not link against $ax_lib !"
+                                exit 202
 			fi
 		fi
 

m4/ax_boost_program_options.m4

@@ -96,10 +96,12 @@ AC_DEFUN([AX_BOOST_PROGRAM_OPTIONS],
                   done
                 fi
             if test "x$ax_lib" = "x"; then
-                AC_MSG_ERROR(Could not find a version of the library!)
+                echo "Could not find a version of the library!"
+                exit 202
             fi
 				if test "x$link_program_options" != "xyes"; then
-					AC_MSG_ERROR([Could not link against [$ax_lib] !])
+					echo "Could not link against [$ax_lib] !"
+                                        exit 202
 				fi
 		fi
 		CPPFLAGS="$CPPFLAGS_SAVED"

m4/ax_boost_unit_test_framework.m4

@@ -124,14 +124,16 @@ AC_DEFUN([AX_BOOST_UNIT_TEST_FRAMEWORK],
                done
             fi
             if test "x$ax_lib" = "x"; then
-                AC_MSG_ERROR(Could not find a version of the library!)
+                echo "Could not find a version of the library!"
+                exit 202
             fi
 			if test "x$link_unit_test_framework" != "xyes"; then
-				AC_MSG_ERROR(Could not link against $ax_lib !)
+				echo "Could not link against $ax_lib !"
+                                exit 202
 			fi
 		fi
 
 		CPPFLAGS="$CPPFLAGS_SAVED"
 	LDFLAGS="$LDFLAGS_SAVED"
 	fi
-])
\ No newline at end of file
+])