crash in axis2_http_sender_configure_proxy_auth

My application crashes in function axis2_http_sender_configure_proxy_auth.

Here is how the proxy is defined in axis2.xml:

<transportSender name="http" class="axis2_http_sender">
<parameter name="PROTOCOL" locked="false">HTTP/1.1</parameter>
<parameter name="xml-declaration" insert="false"/>
<!-parameter name="Transfer-Encoding">chunked</parameter->
<!-parameter name="HTTP-Authentication" username="" password="" locked="true"/->
<parameter name="PROXY" proxy_host="xxxxxx" proxy_port="nnnn" proxy_username="" proxy_password=""
locked="false"/>
</transportSender>

Here is the block where the crash occurs:

if(auth_type)

{ auth_type_end = axutil_strchr(auth_type, ' '); *auth_type_end = AXIS2_ESC_NULL; auth_type_end++; /*Read the realm and the rest stuff now from auth_type_end */ }

Local variables:
force_proxy_auth=0
auth_type="NTLM"

So auth_type_end is NULL and writing to *auth_type_end is invalid.

Here is the full stack trace:
unnamed block in axis2_http_sender_configure_proxy_auth(sender = 0x2003bb28, env = 0x200086c8, msg_ctx = 0x2001fb78, request = 0x2003bdd8), line 3081 in "http_sender.c"
axis2_http_sender_configure_proxy_auth(sender = 0x2003bb28, env = 0x200086c8, msg_ctx = 0x2001fb78, request = 0x2003bdd8), line 3081 in "http_sender.c"
unnamed block in axis2_http_sender_send(sender = 0x2003bb28, env = 0x200086c8, msg_ctx = 0x2001fb78, out = 0x2001fe18, str_url = "http://mellbourn.com/WebServices/PasswordGeneratorWebService/PasswordGeneratorService.asmx", soap_action = "http://www.mellbourn.com/WebServices/get_Password"), line 1194 in "http_sender.c"
axis2_http_sender_send(sender = 0x2003bb28, env = 0x200086c8, msg_ctx = 0x2001fb78, out = 0x2001fe18, str_url = "http://mellbourn.com/WebServices/PasswordGeneratorWebService/PasswordGeneratorService.asmx", soap_action = "http://www.mellbourn.com/WebServices/get_Password"), line 1194 in "http_sender.c"
axis2_http_transport_sender_write_message(transport_sender = 0x2000d628, env = 0x200086c8, msg_ctx = 0x2001fb78, epr = 0x2001f978, out = 0x2001fe18, om_output = 0x2003bae8), line 806 in "http_transport_sender.c"
axis2_http_transport_sender_invoke(transport_sender = 0x2000d628, env = 0x200086c8, msg_ctx = 0x2001fb78), line 309 in "http_transport_sender.c"
unnamed block in axis2_engine_send(engine = 0x2001fca8, env = 0x200086c8, msg_ctx = 0x2001fb78), line 176 in "engine.c"
axis2_engine_send(engine = 0x2001fca8, env = 0x200086c8, msg_ctx = 0x2001fb78), line 176 in "engine.c"
axis2_op_client_two_way_send(env = 0x200086c8, msg_ctx = 0x2001fb78), line 1171 in "op_client.c"
unnamed block in axis2_op_client_execute(op_client = 0x200200c8, env = 0x200086c8, block = 1), line 508 in "op_client.c"
axis2_op_client_execute(op_client = 0x200200c8, env = 0x200086c8, block = 1), line 508 in "op_client.c"
axis2_svc_client_send_receive_with_op_qname(svc_client = 0x200086e8, env = 0x200086c8, op_qname = 0x2001fb38, payload = 0x20008748), line 732 in "svc_client.c"
axis2_svc_client_send_receive(svc_client = 0x200086e8, env = 0x200086c8, payload = 0x20008748), line 830 in "svc_client.c"
main(0x1, 0x2ff21318) at 0x10000644