diff --git a/Configure b/Configure
index fdb75ebbff74dcf98b226d2c878ebd600e8acfa0..1c0df350d15fc8f2570cda0be0d6d6d8f30a505f 100755
--- a/Configure
+++ b/Configure
@@ -475,8 +475,8 @@ my %table=(
 "aix64-gcc","gcc:-maix64 -O -DB_ENDIAN::-pthread:AIX::SIXTY_FOUR_BIT_LONG RC4_CHAR:${ppc64_asm}:aix64:dlfcn:aix-shared::-maix64 -shared -Wl,-G:.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)::-X64",
 # Below targets assume AIX 5. Idea is to effectively disregard $OBJECT_MODE
 # at build time. $OBJECT_MODE is respected at ./config stage!
-"aix-cc",   "cc:-q32 -O -DB_ENDIAN -qmaxmem=16384 -qro -qroconst::-qthreaded:AIX::BN_LLONG RC4_CHAR:${ppc32_asm}:aix32:dlfcn:aix-shared::-q32 -G:.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)::-X 32",
-"aix64-cc", "cc:-q64 -O -DB_ENDIAN -qmaxmem=16384 -qro -qroconst::-qthreaded:AIX::SIXTY_FOUR_BIT_LONG RC4_CHAR:${ppc64_asm}:aix64:dlfcn:aix-shared::-q64 -G:.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)::-X 64",
+"aix-cc",   "cc:-q32 -O -DB_ENDIAN -qmaxmem=16384 -qro -qroconst::-qthreaded -D_THREAD_SAFE:AIX::BN_LLONG RC4_CHAR:${ppc32_asm}:aix32:dlfcn:aix-shared::-q32 -G:.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)::-X 32",
+"aix64-cc", "cc:-q64 -O -DB_ENDIAN -qmaxmem=16384 -qro -qroconst::-qthreaded -D_THREAD_SAFE:AIX::SIXTY_FOUR_BIT_LONG RC4_CHAR:${ppc64_asm}:aix64:dlfcn:aix-shared::-q64 -G:.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR)::-X 64",
 
 #
 # Cray T90 and similar (SDSC)
diff --git a/TABLE b/TABLE
index 7ae1b83c47223803aae90dd522b1c062cfed6c9f..dd9b553b609bc0a3c90a8f8e543ee4e4ce7e43f2 100644
--- a/TABLE
+++ b/TABLE
@@ -862,7 +862,7 @@ $multilib     =
 $cc           = cc
 $cflags       = -q32 -O -DB_ENDIAN -qmaxmem=16384 -qro -qroconst
 $unistd       = 
-$thread_cflag = -qthreaded
+$thread_cflag = -qthreaded -D_THREAD_SAFE
 $sys_id       = AIX
 $lflags       = 
 $bn_ops       = BN_LLONG RC4_CHAR
@@ -961,7 +961,7 @@ $multilib     =
 $cc           = cc
 $cflags       = -q64 -O -DB_ENDIAN -qmaxmem=16384 -qro -qroconst
 $unistd       = 
-$thread_cflag = -qthreaded
+$thread_cflag = -qthreaded -D_THREAD_SAFE
 $sys_id       = AIX
 $lflags       = 
 $bn_ops       = SIXTY_FOUR_BIT_LONG RC4_CHAR