diff --git a/core/src/main/java/org/springframework/ldap/core/DistinguishedName.java b/core/src/main/java/org/springframework/ldap/core/DistinguishedName.java
index d78159a8..5e959c19 100644
--- a/core/src/main/java/org/springframework/ldap/core/DistinguishedName.java
+++ b/core/src/main/java/org/springframework/ldap/core/DistinguishedName.java
@@ -105,6 +105,15 @@ public class DistinguishedName implements Name {
 	 */
 	public static final String SPACED_DN_FORMAT_PROPERTY = "org.springframework.ldap.core.spacedDnFormat";
 
+	/**
+	 * System property that will be inspected to determine whether creating a
+	 * DistinguishedName will leave the keys as they were in the original String
+	 * or convert the keys to lowercase. Default is to convert the keys to
+	 * lowercase.
+	 * @since 1.3.1
+	 */
+	public static final String PRESERVE_KEY_CASE_PROPERTY = "org.springframework.ldap.core.preserveKeyCase";
+
 	private static final Log log = LogFactory.getLog(DistinguishedName.class);
 
 	private static final boolean COMPACT = true;
diff --git a/core/src/main/java/org/springframework/ldap/core/LdapRdnComponent.java b/core/src/main/java/org/springframework/ldap/core/LdapRdnComponent.java
index cdd71ced..63fc60f5 100644
--- a/core/src/main/java/org/springframework/ldap/core/LdapRdnComponent.java
+++ b/core/src/main/java/org/springframework/ldap/core/LdapRdnComponent.java
@@ -51,18 +51,29 @@ public class LdapRdnComponent implements Comparable, Serializable {
 
 	/**
 	 * Constructs an LdapRdnComponent, optionally decoding the value.
+	 * <p>
+	 * If the System property
+	 * <code>org.springframework.ldap.core.preserveKeyCase</code> is set to
+	 * "true", the keys will preserve their original case. Default is to convert
+	 * them to lowercase.
 	 * 
-	 * @param key the Atttribute name.
+	 * @param key the Attribute name.
 	 * @param value the Attribute value.
 	 * @param decodeValue if <code>true</code> the value is decoded (typically
 	 * used when a DN is parsed from a String), otherwise the value is used as
 	 * specified.
+	 * @see DistinguishedName#PRESERVE_KEY_CASE_PROPERTY
 	 */
 	public LdapRdnComponent(String key, String value, boolean decodeValue) {
 		Validate.notEmpty(key, "Key must not be empty");
 		Validate.notEmpty(value, "Value must not be empty");
 
-		this.key = StringUtils.lowerCase(key);
+		String preserveKeyCase = System.getProperty(DistinguishedName.PRESERVE_KEY_CASE_PROPERTY);
+		if (StringUtils.isBlank(preserveKeyCase)) {
+			this.key = StringUtils.lowerCase(key);
+		} else {
+			this.key = key;
+		}
 		if (decodeValue) {
 			this.value = LdapEncoder.nameDecode(value);
 		}
diff --git a/core/src/test/java/org/springframework/ldap/core/DistinguishedNameTest.java b/core/src/test/java/org/springframework/ldap/core/DistinguishedNameTest.java
index 4fbd587b..34c5fc06 100644
--- a/core/src/test/java/org/springframework/ldap/core/DistinguishedNameTest.java
+++ b/core/src/test/java/org/springframework/ldap/core/DistinguishedNameTest.java
@@ -138,7 +138,7 @@ public class DistinguishedNameTest extends TestCase {
 
 		assertEquals("Append failed", "ou=foo,ou=bar,cn=fie,ou=baz", path1.toString());
 	}
-
+	
 	public void testEquals() throws Exception {
 
 		// original object
@@ -581,4 +581,19 @@ public class DistinguishedNameTest extends TestCase {
 			System.setProperty(DistinguishedName.SPACED_DN_FORMAT_PROPERTY, "");
 		}
 	}
+
+	public void testPreserveKeyCasePropertyTrueShouldNotEqualLowerCasedKeys() throws Exception {
+		try {
+			DistinguishedName name = new DistinguishedName("ou=foo,Ou=bar,oU=baz,OU=bim");
+			// First check the default
+			assertEquals("ou=foo,ou=bar,ou=baz,ou=bim", name.toString());
+			System.setProperty(DistinguishedName.PRESERVE_KEY_CASE_PROPERTY, "true");
+			name = new DistinguishedName("ou=foo,Ou=bar,oU=baz,OU=bim");
+			assertEquals("ou=foo,Ou=bar,oU=baz,OU=bim", name.toString());
+		}
+		finally {
+			// Always restore the system setting
+			System.setProperty(DistinguishedName.PRESERVE_KEY_CASE_PROPERTY, "");
+		}
+	}
 }
diff --git a/test/integration-tests/src/test/java/org/springframework/ldap/LdapTemplateModifyITest.java b/test/integration-tests/src/test/java/org/springframework/ldap/LdapTemplateModifyITest.java
index 477927b3..5aa4af33 100644
--- a/test/integration-tests/src/test/java/org/springframework/ldap/LdapTemplateModifyITest.java
+++ b/test/integration-tests/src/test/java/org/springframework/ldap/LdapTemplateModifyITest.java
@@ -159,6 +159,40 @@ public class LdapTemplateModifyITest extends AbstractLdapTemplateIntegrationTest
 		}
 	}
 
+	// LDAP-188
+	@Test
+	public void testModifyAttributes_AddAttributeValueAsDistinguishedName() {
+		try {
+			// prepare test data
+			String dn = "cn=ROLE_USER,ou=groups";
+			String lowerCasedName = "cn=Some Person,ou=company1,c=Sweden,dc=jayway,dc=se";
+			String upperCasedName = "CN=Some Person,OU=company1,C=Sweden,DC=jayway,DC=se";
+			DirContextOperations ctx = tested.lookupContext(dn);
+			ctx.removeAttributeValue("uniqueMember", lowerCasedName);
+			ctx.addAttributeValue("uniqueMember", upperCasedName);
+			tested.modifyAttributes(ctx);
+
+			// without this, the member added above will not be removed and the test fails
+			System.setProperty(DistinguishedName.PRESERVE_KEY_CASE_PROPERTY, Boolean.TRUE.toString());
+			
+			ctx = tested.lookupContext(dn);
+			ctx.removeAttributeValue("uniqueMember", new DistinguishedName(upperCasedName).toCompactString());
+			tested.modifyAttributes(ctx);
+
+			// verify
+			DirContextAdapter result = (DirContextAdapter) tested.lookup(dn);
+			String[] attributes = result.getStringAttributes("uniqueMember");
+			assertEquals(4, attributes.length);
+			assertEquals("0", "cn=Some Person2,ou=company1,c=Sweden,dc=jayway,dc=se", attributes[0]);
+			assertEquals("1", "cn=Some Person,ou=company1,c=Norway,dc=jayway,dc=se", attributes[1]);
+			assertEquals("2", "cn=Some Person,ou=company2,c=Sweden,dc=jayway,dc=se", attributes[2]);
+			assertEquals("3", "cn=Some Person3,ou=company1,c=Sweden,dc=jayway,dc=se", attributes[3]);
+		}
+		finally {
+			System.setProperty(DistinguishedName.PRESERVE_KEY_CASE_PROPERTY, "");
+		}
+	}
+
 	/**
 	 * Test written originally to verify that duplicates are allowed on ordered
 	 * attributes, but had to be changed since Apache DS seems to disallow