CISCO PIC 501 loses connection when NATed

[Smeglor]

I have a Cisco Pix 501 and host a webserver behind it. The problem is recent. When I NAT the webservers IP to a public IP it works fine for several hours in which the server has is able to get traffic in and out and outside users can see the web pages without a problem, but after several hours, ALL public traffic just stops to that web server. Here is my conguration. Any help would be gratly appreciated.

PIX Version 6.3(1)
interface ethernet0 auto
interface ethernet1 100full
nameif ethernet0 outside security0
nameif ethernet1 inside security100
enable password XXXXXXXX encrypted
passwd XXXXXXXXX encrypted
hostname XXXXX
domain-name XXXXXX
fixup protocol ftp 21
fixup protocol h323 h225 1720
fixup protocol h323 ras 1718-1719
fixup protocol http 80
fixup protocol ils 389
fixup protocol rsh 514
fixup protocol rtsp 554
fixup protocol sip 5060
fixup protocol sip udp 5060
fixup protocol skinny 2000
fixup protocol smtp 25
fixup protocol sqlnet 1521
names
access-list outside_access_in permit tcp any host 66.XX.XX.XX eq www
access-list outside_access_in permit icmp any host 66.XX.XX.XX echo
pager lines 24
logging on
mtu outside 1500
mtu inside 1500
ip address outside 66.XX.XX.XX 255.255.255.128
ip address inside 192.168.1.1 255.255.255.0
ip audit info action alarm
ip audit attack action alarm
pdm location 192.168.1.2 255.255.255.255 inside
pdm location 192.168.1.3 255.255.255.255 inside
pdm location 192.168.1.4 255.255.255.255 inside
pdm location 192.168.1.5 255.255.255.255 inside
pdm location 66.XX.XX.XX 255.255.255.255 outside
pdm logging informational 100
pdm history enable
arp timeout 14400
global (outside) 1 interface
nat (inside) 1 0.0.0.0 0.0.0.0 0 0
static (inside,outside) 66.XX.XX.XX 192.168.1.5 netmask 255.255.255.255
0 0
access-group outside_access_in in interface outside
route outside 0.0.0.0 0.0.0.0 66.XX.XX.XX 1
timeout xlate 0:05:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 rpc 0:10:00 h225
1:00:00
timeout h323 0:05:00 mgcp 0:05:00 sip 0:30:00 sip_media 0:02:00
timeout uauth 0:05:00 absolute
aaa-server TACACS+ protocol tacacs+
aaa-server RADIUS protocol radius
aaa-server LOCAL protocol local
http server enable
http 192.168.1.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
telnet 192.168.1.2 255.255.255.255 inside
telnet 192.168.1.3 255.255.255.255 inside
telnet 192.168.1.4 255.255.255.255 inside
telnet timeout 5
ssh timeout 5
console timeout 0
dhcpd address 192.168.1.2-192.168.1.254 inside
dhcpd lease 3600
dhcpd ping_timeout 750
dhcpd auto_config outside
username administrator password XXXXXXXXXXXX encrypted privilege 15
terminal width 80
Cryptochecksum:XXXXXXXXX


I don't know sir...I guess its broke.