diff --git a/core/libs/prx/libc/src/Strings.cpp b/core/libs/prx/libc/src/Strings.cpp
index 18d1df74bc..508da2aa04 100644
--- a/core/libs/prx/libc/src/Strings.cpp
+++ b/core/libs/prx/libc/src/Strings.cpp
@@ -487,7 +487,11 @@ size_t APS5_VABI strspn_nid_postfix(const char* s, const char* accept) {
 }
 
 int APS5_VABI strcoll_nid_postfix(const char* s1, const char* s2) {
-    return std::strcmp(s1, s2);
+    for (;; ++s1, ++s2) {
+        const int a = static_cast<unsigned char>(*s1);
+        const int b = static_cast<unsigned char>(*s2);
+        if (a != b || a == 0) return a - b;
+    }
 }
 
 int APS5_VABI strncpy_s_nid_postfix(char* dest, size_t destsz, const char* src, size_t count) {
diff --git a/core/libs/tests/GuestStrings.cpp b/core/libs/tests/GuestStrings.cpp
index e0effe010e..c7ee8ee32e 100644
--- a/core/libs/tests/GuestStrings.cpp
+++ b/core/libs/tests/GuestStrings.cpp
@@ -176,6 +176,8 @@ static void CheckSecureStringSizeLimits() {
 }
 
 static void CheckCaseInsensitiveComparison() {
+    Require(strcoll_nid_postfix("a", "z") == -25 && strcoll_nid_postfix("z", "a") == 25 && strcoll_nid_postfix("ab", "abc") == -99);
+    Require(strcoll_nid_postfix("A", "a") == -32 && strcoll_nid_postfix("same", "same") == 0 && strcoll_nid_postfix("\xff", "\x01") == 254);
     Require(strcasecmp_nid_postfix("", "") == 0 && strcasecmp_nid_postfix("AbC", "aBc") == 0);
     Require(strcasecmp_nid_postfix("A", "b") == -1 && strcasecmp_nid_postfix("b", "A") == 1);
     Require(strcasecmp_nid_postfix("ab", "A") == 1 && strcasecmp_nid_postfix("AB", "a") == 1);