diff --git a/configure/os/CONFIG.Common.solaris-sparc-gnu b/configure/os/CONFIG.Common.solaris-sparc-gnu
index b89c358c7..6d297404c 100644
--- a/configure/os/CONFIG.Common.solaris-sparc-gnu
+++ b/configure/os/CONFIG.Common.solaris-sparc-gnu
@@ -11,7 +11,7 @@
 include $(CONFIG)/os/CONFIG.Common.solaris-sparc
 # CONFIG.Common.solaris-sparc
 
-COMPILER_CPPFLAGS = 
+COMPILER_CPPFLAGS =  -D_REENTRANT
 
 OP_SYS_LDLIBS_8 = -lc
 OP_SYS_LDLIBS_9 = -lc
diff --git a/configure/os/CONFIG.Common.solaris-x86-gnu b/configure/os/CONFIG.Common.solaris-x86-gnu
index 37244cda9..c7e58cabd 100644
--- a/configure/os/CONFIG.Common.solaris-x86-gnu
+++ b/configure/os/CONFIG.Common.solaris-x86-gnu
@@ -10,7 +10,7 @@
 # Include definitions common to all solaris-x86  target archs
 include $(CONFIG)/os/CONFIG.Common.solaris-x86
 
-COMPILER_CPPFLAGS =
+COMPILER_CPPFLAGS = -D_REENTRANT
 
 OP_SYS_LDLIBS_8 = -lc
 OP_SYS_LDLIBS_9 = -lc