diff --git a/src/misc/pem/pem_pkcs.c b/src/misc/pem/pem_pkcs.c
index 5abf243f4..6a6d4e457 100644
--- a/src/misc/pem/pem_pkcs.c
+++ b/src/misc/pem/pem_pkcs.c
@@ -115,6 +115,7 @@ typedef int (*import_fn)(const unsigned char *, unsigned long, void*);
 static const import_fn s_import_openssl_fns[LTC_PKA_NUM] = {
 #ifdef LTC_MRSA
                                                 [LTC_PKA_RSA] = (import_fn)rsa_import,
+                                                [LTC_PKA_RSA_PSS] = (import_fn)rsa_import,
 #endif
 #ifdef LTC_MDSA
                                                 [LTC_PKA_DSA] = (import_fn)dsa_import,
diff --git a/src/pk/asn1/der/general/der_encode_asn1_length.c b/src/pk/asn1/der/general/der_encode_asn1_length.c
index 7892eea24..e5bf77d62 100644
--- a/src/pk/asn1/der/general/der_encode_asn1_length.c
+++ b/src/pk/asn1/der/general/der_encode_asn1_length.c
@@ -29,7 +29,7 @@ int der_encode_asn1_length(unsigned long len, unsigned char *out, unsigned long
       x >>= 8;
    }
    if (y == 0) {
-      return CRYPT_PK_ASN1_ERROR;
+      y = 1; /* len == 0 is valid: short form, single byte 0x00 */
    }
 
    if (out == NULL) {
diff --git a/tests/pem/pkcs/extra/zerolength.pem b/tests/pem/pkcs/extra/zerolength.pem
new file mode 100644
index 000000000..e6d78fdea
--- /dev/null
+++ b/tests/pem/pkcs/extra/zerolength.pem
@@ -0,0 +1,9 @@
+-----BEGIN PUBLIC KEY-----
+MIIBIjANBgkqhkiG9w0BAQowAAOCAQ8AMIIBCgKCAQEAvTHHoCaR0tlYfvapRv94
+hUTMrdSymIrWIIZ5Kmv5bIYWtK0TMX0icLkB0PzR2IDLj1L7hzBKUljBGzjf6ujf
+Zwru5+odDZ344A6AhH5B5Zie1ALUTnizD+8XtWcdOtv4aF5NwgRJns0YY+HVr/KK
+fPZurfMf7JI2wSCt0TRRUixkfJgypnLNZNMowcMiGD9GYdCb2mC43V8DKNpUIIIU
+JK/auxqAxdEnY6GwI4zYnQdCv8ULai/LcB2CQhj5gm9PeKI6K1qkKs5/F1N2+2y9
+srrSk7pYPU0xxrj5Ap5GsTaJJJhV9QV1bgDiJaakWhh2m9jSs6SsufHCPT5RiCVh
+5QIDAQAB
+-----END PUBLIC KEY-----
\ No newline at end of file