diff --git a/CryptX.xs b/CryptX.xs
index 1d2c726..4180c5a 100644
--- a/CryptX.xs
+++ b/CryptX.xs
@@ -581,7 +581,6 @@
         mp_int mpi;
 
         if (in == NULL || strlen(in) == 0)      XSRETURN_UNDEF;
-
         if (mp_init(&mpi) != CRYPT_OK)          XSRETURN_UNDEF;
 
         if (mp_read_radix(&mpi, in, radix) == CRYPT_OK) {
@@ -624,14 +623,21 @@
           }
           mp_clear(&tmp);
 
-          RETVAL = NEWSV(0, digits + 1);
-          SvPOK_only(RETVAL);
-          out_data = SvPVX(RETVAL);
-          mp_toradix(&mpi, out_data, radix);
-          SvCUR_set(RETVAL, digits);
+          if (digits == 0) {
+            RETVAL = newSVpvn("", 0);
+            mp_clear(&mpi);
+          }
+          else {
+            RETVAL = NEWSV(0, digits + 2); /* +2 for sign and NUL byte */
+            SvPOK_only(RETVAL);
+            out_data = SvPVX(RETVAL);
+            mp_toradix(&mpi, out_data, radix);
+            SvCUR_set(RETVAL, strlen(out_data));
+            mp_clear(&mpi);
+          }
+        }
+        else {
           mp_clear(&mpi);
-        }
-        else {
           XSRETURN_UNDEF;
         }
     }
diff --git a/inc/CryptX_PRNG.xs.inc b/inc/CryptX_PRNG.xs.inc
index d57b0f8..192f1f6 100644
--- a/inc/CryptX_PRNG.xs.inc
+++ b/inc/CryptX_PRNG.xs.inc
@@ -68,7 +68,7 @@
     {
         STRLEN in_len=0;
         unsigned char *in_buffer=NULL;
-        unsigned char entropy_buf[32];
+        unsigned char entropy_buf[40];
         int rv;
         if (SvOK(entropy)) {
           in_buffer = (unsigned char *) SvPVbyte(entropy, in_len);
@@ -76,8 +76,8 @@
           if (rv != CRYPT_OK) croak("FATAL: PRNG_add_entropy failed: %s", error_to_string(rv));
         }
         else {
-          if (rng_get_bytes(entropy_buf, 32, NULL) != 32) croak("FATAL: rng_get_bytes failed");
-          rv = self->desc->add_entropy(entropy_buf, 32, &self->state);
+          if (rng_get_bytes(entropy_buf, 40, NULL) != 40) croak("FATAL: rng_get_bytes failed");
+          rv = self->desc->add_entropy(entropy_buf, 40, &self->state);
           if (rv != CRYPT_OK) croak("FATAL: PRNG_add_entropy failed: %s", error_to_string(rv));
         }
         rv = self->desc->ready(&self->state);
@@ -90,11 +90,11 @@
     {
         int rv_len;
         unsigned char *rdata;
-        unsigned char entropy_buf[32];
+        unsigned char entropy_buf[40];
 
         if (self->last_pid != curpid) {
-          rng_get_bytes(entropy_buf, 32, NULL);
-          self->desc->add_entropy(entropy_buf, 32, &self->state);
+          if (rng_get_bytes(entropy_buf, 40, NULL) != 40) croak("FATAL: rng_get_bytes failed");
+          self->desc->add_entropy(entropy_buf, 40, &self->state);
           self->desc->ready(&self->state);
           self->last_pid = curpid;
         }
@@ -118,11 +118,11 @@
     {
         int i;
         unsigned char rdata[4];
-        unsigned char entropy_buf[32];
+        unsigned char entropy_buf[40];
 
         if (self->last_pid != curpid) {
-          rng_get_bytes(entropy_buf, 32, NULL);
-          self->desc->add_entropy(entropy_buf, 32, &self->state);
+          if (rng_get_bytes(entropy_buf, 40, NULL) != 40) croak("FATAL: rng_get_bytes failed");
+          self->desc->add_entropy(entropy_buf, 40, &self->state);
           self->desc->ready(&self->state);
           self->last_pid = curpid;
         }
@@ -141,12 +141,12 @@
         int i;
         unsigned long a, b;     /* 32bit is enough */
         unsigned char rdata[7]; /* for double we need 53 bits */
-        unsigned char entropy_buf[32];
+        unsigned char entropy_buf[40];
         NV limit;
 
         if (self->last_pid != curpid) {
-          rng_get_bytes(entropy_buf, 32, NULL);
-          self->desc->add_entropy(entropy_buf, 32, &self->state);
+          if (rng_get_bytes(entropy_buf, 40, NULL) != 40) croak("FATAL: rng_get_bytes failed");
+          self->desc->add_entropy(entropy_buf, 40, &self->state);
           self->desc->ready(&self->state);
           self->last_pid = curpid;
         }