HTTPS provisioning server not working

Hi All,

I am having trouble configuring my SoundPoint IP450 with our provisioning server using HTTPS.
Phone is running sip.ld 4.0.4.2906 with a boot of 3.0.2.0024

Provisioning server is configured through DHCP option 160

Unfortunately even if I specify HTTPS, it seems that the phone persist using HTTP
I can see TCP request going towards port 80 instead of 443 as you can see below

000014.080|app1 |3|00|DHCP returned result 0x18F from server 192.168.1.1.
000014.080|app1 |3|00| Phone IP address is 192.168.1.15.
000014.080|app1 |3|00| Subnet mask is 255.255.255.0.
000014.080|app1 |3|00| Gateway address is 192.168.1.1.
000014.080|app1 |3|00| Provisioning server address is https://sipprovisioning.my.domain/.
000014.080|app1 |3|00| DNS server is 8.8.8.8.
000014.080|app1 |3|00| DNS alternate server is 8.8.4.4.
000014.825|copy |3|00|ConfigureCurl : curl option usrpwd is not set
000014.825|dns |3|00|DNS lookup for 'sipprovisioning.my.domain'(XX.XX.XX.XX) TTL=60
000014.825|copy |3|00|'http://:****@sipprovisioning.my.domain/0004f234d2a0.cfg' from 'sipprovisioning.my.domain(XX.XX.XX.XX)'
000022.280|app1 |4|00|Could not load time from 0.0.0.0 (0.0.0.0).



What do I do wrong ?

If I specify the port 443 in my url: https://sipprovisioning.my.domain:443/
I can then see packets going to the proper port, some TLS handshake and the phone ending the connection.
I can't see any logs regarding this connection on my phone