List dhcp_option in hexadecimal

Hello ,

i use Openwrt 18.06 with a Wrt32x

i have to send an option 125 to my isp's tv box

i have to send it in hexadecimal (not writable in text form)

in /etc/config/dhcp :
i try this syntax : list dhcp_option 'X07D,0000ed etc etc.... : it doesn' t work (see not option 125 with tcpdump -Avi)
the syntax `list dhcp_option '125,blabla ...' work (tcpdump see it)

i know that in the /etc/config/network the 'option sendopts X07D:0000ed etc etc.... syntax work well.
but it doesn't work with the interface i need to (static interface)

is it possible to send list dhcp_option in hex format ?
is it a problem with the 18.06 version ?