diff --git a/CMakeLists.txt b/CMakeLists.txt
index 09ad0d2..8158953 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,6 +26,10 @@ IF (CMAKE_SYSTEM MATCHES OS2)
     SET(OS2 TRUE)
 ENDIF (CMAKE_SYSTEM MATCHES OS2)
 
+IF(CMAKE_SYSTEM_NAME STREQUAL "SunOS")
+    SET(SOLARIS TRUE)
+ENDIF(CMAKE_SYSTEM_NAME STREQUAL "SunOS")
+
 INCLUDE(CheckIncludeFile)
 INCLUDE(CheckLibraryExists)
 INCLUDE(CheckCSourceCompiles)
@@ -63,9 +67,9 @@ IF(CMAKE_COMPILER_IS_GNUCC)
     " PHYSFS_IS_GCC4)
 
     IF(PHYSFS_IS_GCC4)
-        IF (NOT OS2)  # Not supported on OS/2.
+        IF((NOT OS2) AND (NOT SOLARIS)) # Not supported on OS/2 or Solaris.
             ADD_DEFINITIONS(-fvisibility=hidden)
-        ENDIF (NOT OS2)
+        ENDIF((NOT OS2) AND (NOT SOLARIS))
     ENDIF(PHYSFS_IS_GCC4)
 ENDIF(CMAKE_COMPILER_IS_GNUCC)