diff --git a/phpseclib/Crypt/Blowfish.php b/phpseclib/Crypt/Blowfish.php
index 3949e812..27e34b75 100644
--- a/phpseclib/Crypt/Blowfish.php
+++ b/phpseclib/Crypt/Blowfish.php
@@ -317,7 +317,7 @@ class Blowfish extends Base
     function isValidEngine($engine)
     {
         if ($engine == self::ENGINE_OPENSSL) {
-            if ($this->key_length != 16) {
+            if ($this->key_length < 16) {
                 return false;
             }
             $this->cipher_name_openssl_ecb = 'bf-ecb';
diff --git a/phpseclib/Crypt/RC4.php b/phpseclib/Crypt/RC4.php
index 1e768d7d..51033320 100644
--- a/phpseclib/Crypt/RC4.php
+++ b/phpseclib/Crypt/RC4.php
@@ -144,21 +144,8 @@ class RC4 extends Base
      */
     function isValidEngine($engine)
     {
-        switch ($engine) {
-            case Base::ENGINE_OPENSSL:
-                switch (strlen($this->key)) {
-                    case 5:
-                        $this->cipher_name_openssl = 'rc4-40';
-                        break;
-                    case 8:
-                        $this->cipher_name_openssl = 'rc4-64';
-                        break;
-                    case 16:
-                        $this->cipher_name_openssl = 'rc4';
-                        break;
-                    default:
-                        return false;
-                }
+        if ($engine == Base::ENGINE_OPENSSL) {
+            $this->cipher_name_openssl = 'rc4-40';
         }
 
         return parent::isValidEngine($engine);
diff --git a/tests/Unit/Crypt/BlowfishTest.php b/tests/Unit/Crypt/BlowfishTest.php
index bf15feb8..c523425d 100644
--- a/tests/Unit/Crypt/BlowfishTest.php
+++ b/tests/Unit/Crypt/BlowfishTest.php
@@ -84,4 +84,47 @@ class Unit_Crypt_BlowfishTest extends PhpseclibTestCase
         $plaintext = bin2hex($plaintext);
         $this->assertEquals($result, $expected, "Failed asserting that $plaintext yielded expected output in $engineName engine");
     }
+
+    public function testKeySizes()
+    {
+        $objects = $engines = array();
+        $temp = new Blowfish(Base::MODE_CTR);
+        $temp->setPreferredEngine(Base::ENGINE_INTERNAL);
+        $objects[] = $temp;
+        $engines[] = 'internal';
+
+        if ($temp->isValidEngine(Base::ENGINE_MCRYPT)) {
+            $temp = new Blowfish(Base::MODE_CTR);
+            $temp->setPreferredEngine(Base::ENGINE_MCRYPT);
+            $objects[] = $temp;
+            $engines[] = 'mcrypt';
+        }
+
+        if ($temp->isValidEngine(Base::ENGINE_OPENSSL)) {
+            $temp = new Blowfish(Base::MODE_CTR);
+            $temp->setPreferredEngine(Base::ENGINE_OPENSSL);
+            $objects[] = $temp;
+            $engines[] = 'OpenSSL';
+        }
+
+        if (count($objects) < 2) {
+            self::markTestSkipped('Unable to initialize two or more engines');
+        }
+
+        for ($i = 0; $i < count($objects); $i++) {
+            $objects[$i]->setIV(str_repeat('x', $objects[$i]->getBlockLength() >> 3));
+        }
+
+        $plaintext = str_repeat('.', 100);
+
+        for ($keyLen = 4; $keyLen <= 56; $keyLen++) {
+            $key = crypt_random_string($keyLen);
+            $objects[0]->setKey($key);
+            $ref = $objects[0]->encrypt($plaintext);
+            for ($i = 1; $i < count($objects); $i++) {
+                $objects[$i]->setKey($key);
+                $this->assertEquals($ref, $objects[$i]->encrypt($plaintext), "Failed asserting that {$engines[$i]} yields the same output as the internal engine with a key size of $keyLen");
+            }
+        }
+    }
 }
diff --git a/tests/Unit/Crypt/RC4Test.php b/tests/Unit/Crypt/RC4Test.php
index 1a020ff8..ce16b13f 100644
--- a/tests/Unit/Crypt/RC4Test.php
+++ b/tests/Unit/Crypt/RC4Test.php
@@ -209,4 +209,43 @@ class Unit_Crypt_RC4Test extends PhpseclibTestCase
         $result = $rc4->encrypt(str_repeat("\0", $offset + 16));
         $this->assertEquals(bin2hex(substr($result, -16)), $expected, "Failed asserting that key $key yielded expected output at offset $offset in $engineName engine");
     }
+
+    public function testKeySizes()
+    {
+        $objects = $engines = array();
+        $temp = new RC4(Base::MODE_CTR);
+        $temp->setPreferredEngine(Base::ENGINE_INTERNAL);
+        $objects[] = $temp;
+        $engines[] = 'internal';
+
+        if ($temp->isValidEngine(Base::ENGINE_MCRYPT)) {
+            $temp = new RC4(Base::MODE_CTR);
+            $temp->setPreferredEngine(Base::ENGINE_MCRYPT);
+            $objects[] = $temp;
+            $engines[] = 'mcrypt';
+        }
+
+        if ($temp->isValidEngine(Base::ENGINE_OPENSSL)) {
+            $temp = new RC4(Base::MODE_CTR);
+            $temp->setPreferredEngine(Base::ENGINE_OPENSSL);
+            $objects[] = $temp;
+            $engines[] = 'OpenSSL';
+        }
+
+        if (count($objects) < 2) {
+            self::markTestSkipped('Unable to initialize two or more engines');
+        }
+
+        $plaintext = str_repeat('.', 100);
+
+        for ($keyLen = 5; $keyLen <= 256; $keyLen++) {
+            $key = crypt_random_string($keyLen);
+            $objects[0]->setKey($key);
+            $ref = $objects[0]->encrypt($plaintext);
+            for ($i = 1; $i < count($objects); $i++) {
+                $objects[$i]->setKey($key);
+                $this->assertEquals($ref, $objects[$i]->encrypt($plaintext), "Failed asserting that {$engines[$i]} yields the same output as the internal engine with a key size of $keyLen");
+            }
+        }
+    }
 }