diff --git a/mozilla/security/coreconf/WIN954.0.mk b/mozilla/security/coreconf/WIN954.0.mk
index 12a6652a7a0..ba9e7011440 100644
--- a/mozilla/security/coreconf/WIN954.0.mk
+++ b/mozilla/security/coreconf/WIN954.0.mk
@@ -68,3 +68,6 @@ ifndef MOZ_DEBUG_SYMBOLS
 endif
 endif
 DEFINES += -DWIN95
+
+# WINNT uses the lib prefix, Win95 and WinCE don't
+NSPR31_LIB_PREFIX = $(NULL)
diff --git a/mozilla/security/coreconf/WINCE3.0.mk b/mozilla/security/coreconf/WINCE3.0.mk
index 95eb9b6ac86..7e4ec7addb4 100644
--- a/mozilla/security/coreconf/WINCE3.0.mk
+++ b/mozilla/security/coreconf/WINCE3.0.mk
@@ -104,4 +104,4 @@ DLLBASE += -align:"4096"
 #DEFINES += -DWINNT
 
 # WINNT uses the lib prefix, Win95 and WinCE don't
-#NSPR31_LIB_PREFIX = lib
+NSPR31_LIB_PREFIX = $(NULL)