diff --git a/Makefile.config.in b/Makefile.config.in
index 4a6b6cf1..47229732 100644
--- a/Makefile.config.in
+++ b/Makefile.config.in
@@ -139,7 +139,7 @@ CONFIG_OWN_LIBC = @CONFIG_OWN_LIBC@
 CONFIG_SCRIPTING_PERL = @CONFIG_SCRIPTING_PERL@
 CONFIG_POD2HTML = @CONFIG_POD2HTML@
 CONFIG_SCRIPTING_PYTHON = @CONFIG_SCRIPTING_PYTHON@
-CONFIG_RISCOS = @CONFIG_RISCOS@
+CONFIG_OS_RISCOS = @CONFIG_OS_RISCOS@
 CONFIG_SCRIPTING_RUBY = @CONFIG_SCRIPTING_RUBY@
 CONFIG_SCANNER = @CONFIG_SCANNER@
 CONFIG_SCRIPTING = @CONFIG_SCRIPTING@
diff --git a/configure.in b/configure.in
index 242db08b..e88cb060 100644
--- a/configure.in
+++ b/configure.in
@@ -145,8 +145,8 @@ kill me!
 EL_CHECK_COMPILER_MACROS(CONFIG_BEOS, [BEOS], [__BEOS__])
 AC_SUBST(CONFIG_BEOS)
 
-EL_CHECK_COMPILER_MACROS(CONFIG_RISCOS, [RISCOS], [__riscos__])
-AC_SUBST(CONFIG_RISCOS)
+EL_CHECK_COMPILER_MACROS(CONFIG_OS_RISCOS, [RISCOS], [__riscos__])
+AC_SUBST(CONFIG_OS_RISCOS)
 
 EL_CHECK_COMPILER_MACROS(CONFIG_WIN32, [WIN32], [_WIN32 __WIN32__])
 AC_SUBST(CONFIG_WIN32)
@@ -158,7 +158,7 @@ test "$CONFIG_OS_OS2" = yes && LDFLAGS=`echo "$LDFLAGS" | sed "s/-Zexe//g"`
 AC_MSG_CHECKING([for UNIX])
 dnl FIXME: some depend kind of mechanism
 if test "$CONFIG_BEOS" = no && \
-   test "$CONFIG_RISCOS" = no && \
+   test "$CONFIG_OS_RISCOS" = no && \
    test "$CONFIG_WIN32" = no && \
    test "$CONFIG_OS_OS2" = no; then
 	EL_CONFIG(CONFIG_UNIX, [UNIX])
diff --git a/src/ecmascript/spidermonkey/util.h b/src/ecmascript/spidermonkey/util.h
index 9caf547f..d2d49e3f 100644
--- a/src/ecmascript/spidermonkey/util.h
+++ b/src/ecmascript/spidermonkey/util.h
@@ -7,7 +7,7 @@
 #define XP_BEOS
 #elif CONFIG_OS_OS2
 #define XP_OS2
-#elif CONFIG_RISCOS
+#elif CONFIG_OS_RISCOS
 #error Out of luck, buddy!
 #elif CONFIG_UNIX
 #define XP_UNIX
diff --git a/src/osdep/Makefile b/src/osdep/Makefile
index c8187f76..c4e1f282 100644
--- a/src/osdep/Makefile
+++ b/src/osdep/Makefile
@@ -4,7 +4,7 @@ INCLUDES += $(X_CFLAGS)
 
 SUBDIRS-$(CONFIG_BEOS)		+= beos
 SUBDIRS-$(CONFIG_OS_OS2)		+= os2
-SUBDIRS-$(CONFIG_RISCOS)	+= riscos
+SUBDIRS-$(CONFIG_OS_RISCOS)	+= riscos
 SUBDIRS-$(CONFIG_UNIX)		+= unix
 SUBDIRS-$(CONFIG_WIN32)		+= win32
 
diff --git a/src/osdep/osdep.c b/src/osdep/osdep.c
index a8b74f64..dd65431c 100644
--- a/src/osdep/osdep.c
+++ b/src/osdep/osdep.c
@@ -232,7 +232,7 @@ get_terminal_size(int fd, int *x, int *y)
 
 /* Pipe */
 
-#if defined(CONFIG_UNIX) || defined(CONFIG_BEOS) || defined(CONFIG_RISCOS)
+#if defined(CONFIG_UNIX) || defined(CONFIG_BEOS) || defined(CONFIG_OS_RISCOS)
 
 void
 set_bin(int fd)
@@ -729,7 +729,7 @@ init_osdep(void)
 
 #endif
 
-#if defined(CONFIG_UNIX) || defined(CONFIG_OS_OS2) || defined(CONFIG_RISCOS)
+#if defined(CONFIG_UNIX) || defined(CONFIG_OS_OS2) || defined(CONFIG_OS_RISCOS)
 
 void
 terminate_osdep(void)
@@ -823,7 +823,7 @@ get_common_env(void)
 }
 #endif
 
-#if defined(CONFIG_UNIX) || defined(CONFIG_RISCOS)
+#if defined(CONFIG_UNIX) || defined(CONFIG_OS_RISCOS)
 int
 get_system_env(void)
 {
diff --git a/src/osdep/riscos/riscos.h b/src/osdep/riscos/riscos.h
index 0232d054..0acb126e 100644
--- a/src/osdep/riscos/riscos.h
+++ b/src/osdep/riscos/riscos.h
@@ -2,7 +2,7 @@
 #ifndef EL__OSDEP_RISCOS_RISCOS_H
 #define EL__OSDEP_RISCOS_RISCOS_H
 
-#ifdef CONFIG_RISCOS
+#ifdef CONFIG_OS_RISCOS
 
 /* TODO */
 
diff --git a/src/osdep/riscos/sysinfo.h b/src/osdep/riscos/sysinfo.h
index e7c2cdba..107ccf5f 100644
--- a/src/osdep/riscos/sysinfo.h
+++ b/src/osdep/riscos/sysinfo.h
@@ -2,7 +2,7 @@
 #ifndef EL__OSDEP_RISCOS_SYSINFO_H
 #define EL__OSDEP_RISCOS_SYSINFO_H
 
-#ifdef CONFIG_RISCOS
+#ifdef CONFIG_OS_RISCOS
 
 #define SYSTEM_NAME	"RISC OS"
 #define SYSTEM_STR	"riscos"
diff --git a/src/osdep/system.h b/src/osdep/system.h
index 9cd72c46..c3c138fb 100644
--- a/src/osdep/system.h
+++ b/src/osdep/system.h
@@ -3,7 +3,7 @@
 
 #if !defined(CONFIG_BEOS) \
      && !defined(CONFIG_OS_OS2) \
-     && !defined(CONFIG_RISCOS) \
+     && !defined(CONFIG_OS_RISCOS) \
      && !defined(CONFIG_UNIX) \
      && !defined(CONFIG_WIN32)