The right-back, who made his first team breakthrough earlier this season, has been out of action since damaging his knee while on international duty with New Zealand in November.
Graham tore his anterior cruciate ligament and required surgery.
In Caldwell’s first month at the Proact he didn’t appear to be up to speed on Graham’s whereabouts or injury status.
When asked about the full-back he said: “He’s not back yet and I don’t think he’ll come back for the foreseeable future.”
But the defender did return to the club midway through last month, seemingly having been recovering from surgery in Dubai.
The Spireites manager has previously stated that players were in control of their futures at the club and could earn new deals through performances.
Graham is still in the rehabilitation phase of his recovery and as such unable to impress the manager on the pitch at present.
But Caldwell has offered some hope to the 24-year-old.
“It’s important he gets fit,” said the Scot.
“I think he’s working very hard and I’ve seen him about the place, which is good, I’ve come into contact with him now.
“It’s important he gets fit and when we come back in pre-season that will be an opportunity for him to show what he can do and what he can bring to the club.”
Graham played six times for Town this season and picked up four international caps before his injury.
Last season he spent his time in the reserves and on loan at non-league Whitehawk.